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МІНІСТЕРСТВО ОСВІТИ І НАУКИ УКРАЇНИ ТЕЧНІЧНИЙ КОЛЕДЖ ЛУЦЬКОГО НАЦІОНАЛЬНОГО ТЕХНІЧНОГО УНІВЕРСИТЕТУ ІНОЗЕМНА МОВА ЗА ПРОФЕСІЙНИМ СПРЯМУВАННЯМ МЕТОДИЧНІ РЕКОМЕНДАЦІЇ ДО виконання самостійної роботи ДЛЯ СТУДЕНТІВ ІІІ КУРСУ СПЕЦІАЛЬНОСТІ 5.05010201 «ОБСЛУГОВУВАННЯ КОМП’ЮТЕРНИХ СИСТЕМ І МЕРЕЖ» НАПРЯМ ПІДГОТОВКИ 050102 «КОМП’ЮТЕРНА ІНЖЕНЕРІЯ» ДЕННОЇ ФОРМИ НАВЧАННЯ Редакційно-видавничий відділ Луцького національного технічного університету Луцьк 2013 1 УДК 811.111:004 ББК 81.432.1+32.973 Семенюк Я. О. Іноземна мова за професійним спрямуванням: методичні рекомендації до виконання самостійної роботи для студентів ІІІ курсу спеціальності 5.05010201 «ОБСЛУГОВУВАННЯ КОМП’ЮТЕРНИХ СИСТЕМ І МЕРЕЖ», напрямку підготовки 050102 «КОМП’ЮТЕРНА ІНЖЕНЕРІЯ», призначені для денної форми навчання технічного коледжу Луцького національного технічного університету. – Луцьк, 2013. – 56с. Укладач: Я.О. Семенюк. Рецензент: Т.А. Крисанова Відповідальний за випуск: Т.М. Бондарук Затверджено науково-методичною радою Луцького НТУ, протокол №____ від « »__________ 2013 р. Рекомендовано до друку науково-методичною радою ТК Луцького НТУ, протокол №____ від « »__________ 2013 р. Комп’ютерна верстка: Семенюк Я.О. © Технічний коледж Луцького національного технічного університету, 2013 © Семенюк Я.О. 2 Зміст Вступ ......................................................................................................................... 4 1. Theme: Future Technique ..................................................................................... 5 2. Theme: Operating System ................................................................................... 13 3. Theme: Computers’ Development History ......................................................... 28 4. Theme: Surf the Net ............................................................................................ 37 5. Theme: Grammar: Direct and Indirect Speech ................................................... 40 6. Theme: The Web ................................................................................................. 44 7. Theme: Grammar: First and Second Conditional ............................................... 46 Література .............................................................................................................. 54 NOTES .................................................................................................................... 55 3 Вступ Сьогодні освіта розглядається як процес становлення особистості, яка здатна до саморозвитку, самоосвіти, творчого розв’язання проблем, критичного мислення, ось чому роль викладача полягає в педагогічній підтримці розвитку студентів. Самостійна робота являється одним з засобів формування якостей, які притаманні самоорганізованій та самодисциплінованій особистості, а самоорганізація відображає свідому роботу студентів над собою з метою самовдосконалення та розвитку пізнавальних, практичних, емоційних, моральних, вольових здібностей та рис характеру, являється важливим компонентом в процесі професійної підготовки. Метою вивчення іноземної мови за професійним спрямуванням на немовних факультетах є якісна підготовка фахівця у професійній сфері на основі світового досвіду з використанням тематичного матеріалу, передбаченого програмою даного курсу. Це: 1)систематизація та розширення словникового запасу студентів з професійних тем комп’ютерного спрямування; 2) навчання студентів правильно вживати вивчені лексичні одиниці в усному мовленні; 3) розвиток логічного, аналітичного мислення, оволодіння певною термінологією професійного спрямування та застосовування її на практиці, розширення світогляду студентів; 4) розвиток уваги, пам’яті, уяви, інтелекту студентів, мовної здогадки; 5) виховання особистості, яка персонально відповідатиме за свій освітній та професійний рівень та інтерес до обраної професії. Кінцевою метою навчальнометодичних рекомендацій є підготовка до проміжного контролю у формі тестових завдань. Мовний матеріал максимально узгоджений з потребами студентів, в даному випадку, зі спеціальністю 5.05010201 «ОБСЛУГОВУВАННЯ КОМП’ЮТЕРНИХ СИСТЕМ І МЕРЕЖ». Дані навчально-методичні рекомендації побудовані на принципах особистісноорієнтованого навчання, а саме : індивідуалізація, спіралеподібна побудова навчального матеріалу, постійна самооцінка студента, динаміка просування до успіху, максимальне наближення навчального матеріалу до життя. Структурно навчально-методичні рекомендації складаються з 7-ми тем, які містять в собі матеріал навчальних семестрів, (денна форма навчання), а також список використаної літератури. Навчально-методичні рекомендації призначаються для студентів III курсу, спеціальності 5.05010201 «ОБСЛУГОВУВАННЯ КОМП’ЮТЕРНИХ СИСТЕ І МЕРЕЖ», напрямку підготовки 050102 «КОМП’ЮТЕРНА ІНЖЕНЕРІЯ». Вони можуть також використовуватись викладачами вищих навчальних закладів нефілологічних спеціальностей, а також особами, що самостійно вивчають англійську мову. 4 1. Theme: Future Technique Future Technique Since the beginning of time technology has helped us out as a human race. From the invention of the wheel to the Internet, technology has been a great factor on the way our civilization has grown. With more and more technological advances just around the corner, our civilization will continue to grow faster and faster than ever before. People often think that future is all about flying cars, robots and space travelling. Maybe it will be like that, who knows, but at least until this day the changes haven’t been remarkable. Companies are all the time investing more money on research and development. This indicates that companies and government are interested to achieve and find new technological inventions that would change the markets. All ready one of the computer related inventions, Internet, has changed the spreading of information globally. Internet is worldwide network of connected computers. This network enables you to communicate with the rest of the world in different ways? Has been approximated that the total amount of information globally doubles every 18 months, which indicates that internet, as an important part of media nowadays, affects everyone of us thought we might not have a possibility to be on-line. The approximated number of people who are on-line daily is more than 18%? Internet is not only a way to spend time surfing, but it is also an very good way to make money by transforming products, services and markets. It is an easy way to reach people when thinking advertising and it is an easy way to people to reach the information wanted, but the competition between companies in the virtual reality of Internet, is as hard as in the real world. Government’s space program also influences and will influence economics of the future. U.S. government’s NASA (North American Space Association) has done great job exploring space and research new opportunities in outer space and other planets. The question is how the new future technology will change the direction of economics and by that our living on Earth or maybe on some other planet? The world population is growing fast. The room to live on earth might be a problem in future, and Earth might not be able to feed the upcoming population. This is one of the reasons why we have to explore the space for new opportunities. The greatest effect of future technology has is on the productivity. Technological change, or innovation, is a contributor to the growth of productivity. From the development of plows to the invention of computers, history shows many examples of technologies that have increased productivity. New products, new methods of production, new ways of organizing production or marketing products and new methods of communication can each demonstrate how productivity increases. This makes people’s everyday life easier and the quality of living is higher. One example how technological change has changed our living past 10 years have been reusable products and materials. Recycling and reusable materials have made our quality of living better by minimizing the production of trash. Also the technological changes in agriculture have increased productivity of our basic need products. No one knows what’s going to happen in the future, but the new future technology can at least give us a direction. Our actions have a great effect how we and the upcoming generations are going to live on Earth. Putting money now on research and development gives a better economics base that we can rely on. The biggest change to our economic will have the increased productivity. By increased productivity our standard of living will be higher and our everyday life will be easier. May every one of us be there to witness the flying cars and talking robots, so that we can be proud of our achievements? 5 Computers’ Future Moore's law predicts that the numbers of discrete elements on a square-inch silicon integrated circuit will double every two years. While it's not exactly a direct relationship, you can interpret that to mean that computers will double in processing power every two years. That means in the years between 2010 and 2050, computer processing power will double 20 times if Moore's law holds true. In 2010, IBM introduced the zEnterprise 196 (z196), which boasted a processor capable of running at 5.2 gigahertz (GHz) -- the fastest commercially available processor at that time. That means the z196 processor ran at 5.2 billion cycles per second. Every instruction a processor executes requires a set number of clock ticks. The more clock ticks a processor squeezes into a second, the more instructions that processor can complete in a given amount of time. That's what we mean when we say a 5.2-GHz processor is faster than a 3.2-GHz processor -- the 5.2-GHz microchip is capable of executing more instructions than the 3.2-GHz chip in the same amount of time. If 5.2 GHz was the top speed in 2010, what will it be in 2050? Assuming engineers can find ways to keep up with Moore's law and processor speed actually doubles every 24 months, by 2050 we'd have a chip capable of running at 5,452,595 gigahertz, or nearly 5.5 pet hertz. It's hard to imagine what kind of applications we could direct such a machine to tackle. Complex computational problems, such as building virtual simulations of the human brain, may become a relatively simple task. Some futurists believe we may even create machines with intelligence far greater than our own. Perhaps those machines could discover ways to improve processing speeds even faster than humans can. Before long, you could have a self-improving device pushing the physical limits of how fast machines can process information. While this dream of the future is popular among a certain segment of computer scientists and futurists, other people are more skeptical. Perhaps the human mind is far more complex than we understand. Thinking may involve more than just electrochemical messages passed between neurons. Perhaps there's a hormonal element that subtly shapes how we think. If that's the case, it may be that pure computational horsepower won't be enough to create a machine capable of what we consider thought. Setting aside the artificial intelligence debate for a moment, what might futuristic computers look like? They might actually be invisible. Pervasive computing is a type of technology that incorporates computers into just about anything you can imagine. Buildings, highways, vehicles and even the clothing you wear might have built-in computer elements. Coupled with networking technology, the world of 2050 may be one in which the very environment around you is part of a massive computing system. In such a world, your digital life and your real life could overlap seamlessly. We see hints of this world in today's technology. There are hundreds of smart phone applications that add a digital layer over our perception of the real world. They might help you navigate around a strange city or discover a new favorite restaurant tucked away in a corner somewhere. These applications still require us to activate programs on mobile devices and use those devices as a lens through which we can see the digital world. In the future, we may be able to accomplish the same thing using glasses, contact lenses or perhaps even ocular implants. Imagine being able to look at the world through one of a million different filters, all of which provide different kinds of information to you instantaneously. Then again, it's possible that our ingenuity won't be enough to keep up with Moore's law after a few more microprocessor generations. Perhaps our computers will be more mundane and functional. But considering the way they've transformed our world over the last 50 years, I'm willing to bet 2050 will be an exotic, digital era. What do you think? 6 Gadgets from the Near Future Keyboard Puzzle Many PC users often complain that they can not choose a keyboard to your taste, or complain about the huge amount of unused buttons. Conceptual Puzzle Keyboard just for them. This device has a structure of a puzzle. In other words, you will have the ability to completely customize the keyboard, some keys to remove completely, while others moved to a more convenient location, tilt it for better ergonomics. Puzzle Keyboard also can interact with mobile devices, or used as a wired remote management. Mouse for Innovators If you are tired of the classic mice, similar to each other and only slightly different in appearance. Or touchpad for you – is not an option. Then, a new development company, called Evergreen DN-45545 – this is what you need. We present you a very strange gadget that is unlike any other device. But this also is a computer mouse. Forget about the horizontal position arm on a mouse – in this way a mouse you can not keep. Imagine a better, that keep your hands stick to flight simulation – it will be the most convincing comparison. As the developers, they have spent a lot of time working on the ergonomics of the housing Evergreen DN-45545. Developers have this perfect device. As a result, the mouse received a highly original form, and its surface is almost completely covered with rubber. Package also includes a cradle under the brush, but it can be removed. Equipment Evergreen DN-45545 has four function keys. Separately, there is a button switch sensor resolution and the scroll wheel. The maximum resolution of the sensor is 1600 dpi. DN-45545 is a manipulator with wire cable 1.5 meters. Device weighs 160 grams and has dimensions 135h100h82 millimeter. Smart Highway Now the roads are not just roads, but be smart. Two Dutch design studios Roosegaarde and Heijmans developed stunning project a "smart way." It includes a number of interactive technologies that adapt to traffic conditions and visually show drivers of useful information. 7 The main technological element of the road of the future – the paint. In this respect, the Dutch ahead over Europe. A few years ago, they got the "nano-paint", which can be controlled with the remote control – press the blue button and the wall paint, turned blue, red – red, etc. The concept of the new Dutch road uses a combination of sensors, special inks and high-tech batteries that collect energy from the wind of passing vehicles. «Smart Highway» will become reality in 2013. Road paint «Dynamic Paint» sensitive to temperature. In normal weather conditions, the paint is transparent, but when the temperature drops and the road is slippery, the paint shows warning signs of danger. «Glow-in-the-Dark Road» – fluorescent dye that absorbs sunlight during the day and light up to 10 hours at night, which increases visibility and reduces the need for additional lighting. Another technique is called "Interactive Light". It uses sensors to detect an oncoming car, if a car is approaching, the road begins to glow brighter and fades when the vehicle is removed. Thus, the road will turn on only when needed, and will not waste expend energy reserve. "Smart Highway" was named best concept. «Project Glass» by Google Google has demonstrated a prototype of the concept points «Project Glass», which will replace the phone, tablet and GPS-navigator. According to employees of the company, Google goggles will be available in late 2012. One lucky man who has tried the concept of points «Project Glass», said: "These technologies have allowed to come into our lives. In order to take a picture, I do not need flattery in his pocket for phone and just press the button at the top of the points, that’s all. " Sony PSP 2 with a Transparent OLED-display A year ago, Sony has released a portable console PS Vita. It a branded gaming gadget second generation with a productive processor and a bunch of ways to control gameplay. PS Vita sales were not as serious as we would like, but the device has found its place in the market and feels quite decent. What will happen when the time comes to make another big step forward? 8 This question was answered by of the designer Jung Ou Yang. He introduced the concept of the portable console Sony PSP 2. The most notable advantage of the toys is transparent 5-inch OLED-display. The era of these screens is not yet come, but now is the time of the revolution. It would be possible to begin a large-scale attack and with the portable consoles. On each side of the display has the traditional controls. Make them transparent obviously is no need. Other specifications Sony PSP 2 look as dignified. There is a full set of wireless protocols including Bluetooth, Wi-Fi and 3G, the main and front camera as well as a more powerful processor than the 4-core chip in the real PS Vita. Maybe a couple of years Sony could well produce something like that in reality. Folding Tablet Wallet – a unique folding device that can function as a phone, tablet and camera. Due to its design the gadget easily fits in your pocket. Wallet is made up of three parts, each with stocked a display. Fold the device can be on the basis of a screen. The case is made of durable innovative material Technogel. The device is equipped with a camera with a resolution of 12.1 megapixels and video recording HD 1080p, has a headphone jack and a micro-USB type B, through which you can connect to virtually any peripheral components (mouse, keyboard, printer, even a TV). Unusual Concept LG Hi-Fi Unusual concept is a real dream of music lovers: it can be used as the phone, and as stereo. Turn the device to the headphones can one movement hand. MP3 player, as and the drive is built into the represented gadget. In the prototype use the touch screen that takes up the entire front panel when folded. True, on images no microphone, but if LG Hi-Fi sometime will see the light, this and other minor disadvantages, of course, will be eliminated. Smartphone with Perfect Ergonomics Mobile phones with touch screens have taught us to look at the interaction with the gadgets a completely new way. The touch interface allows you manage graphics directly on 9 screen mobile. But is it comfortable and stayed there still potential for growth? These questions try answer Korean designer Wauseon Such to the concept phone Another World. A distinctive feature of the mobile phone Another World is that it is entirely covered a touch screen. According to the author, this is the best way to optimize the multi-touch interface, the user is not required to make any unnecessary movements to perform the required actions, virtual buttons can appear at any point of the phone. On the lower half of the front panel of Another World posted additional control element, which is also at the center is a small touch screen. With this solution, you will never miss all the most important thing. It is worth noting the original mode of performance interface, this is not the traditional icons or widgets, straight lines extending radically from a central element. It is a pity that in the foreseeable future, the market does not appear anything like this. Exercise1 Match the following headings to their appropriate paragraphs a) Home Computers b) From Tubes to Tablets c) Tablets d) Laptops, Netbooks and Ultrabooks e) In 2020 we can wear Sony Computers on our Wrists ………………………………………………………………………………………...…………… Recent innovations such as the iPod provide an exciting glimpse into the future of computers. Before looking forward toward future computer trends, let's take a quick look back to gain a better appreciation of the evolution thus far. Do you remember when the first primitive computing machines occupied entire buildings? The massive machines from the mid-20th century consisted of row upon row of vacuum tubes and wires. You had to use stacks of punch cards to program these beasts. Today's computers operate using transistors, wires and electricity. Future computers might use atoms, fibers and light. Personally, I don't give a byte what makes it tick, as long as it does the job. If I could accidentally spill my coffee and not have it cost $848, that would be a cool feature. But let us assume that you are not still bitter from a recent laptop replacement. You might stop to consider what the world might be like, if computers the size of molecules become a reality. These are the types of computers that could be everywhere, but never seen. Nano sized bio-computers that could target specific areas inside your body. Giant networks of computers, in your clothing, your house, your car. Entrenched in almost every aspect of our lives and yet you may never give them a single thought. Understanding the theories behind these future computer technologies is not for the meek. My research into quantum computers was made all the more difficult after I learned that in light of her constant interference, it is theoretically possible my mother-in-law could be in two places at once. 10 If you have the heart, take a gander at the most promising new computer technologies. If not, dare to imagine the ways that billions of tiny, powerful computers will change our society. ....................................................................................................................... Steve Jobs and Bill Gates were both instrumental in bringing the computer down to size. With the introduction of the personal computer and its widespread acceptance, computers shrunk while processing power increased. Even the bulky CRT monitors got a makeover with flat LCD monitors now the norm. In addition, costs have fallen so much over the years that many households own several personal computers and wireless networks. Future technology won't necessarily render the home PC obsolete, but it will change it. For example, modern televisions and appliances are now Web-enabled. Expect future technology to blend appliances into the home network. I must admit that in some ways I envy Donald Trump. Not because of all the real estate he owns or even for his cool private helicopter. No, what I envy most about The Donald is his apprentice. Who wouldn't appreciate giving any chore that comes to mind, to an eager and competent assistant? After time, a good apprentice might even anticipate your needs. "Pink tie today, Mr. Trump?". Now apply this same kind of relationship model to the future of computing. In the future, the number of tiny but powerful computers you encounter every day will number in the thousands, perhaps millions. You won't see them, but they will be all around you. Your personal interface to this powerful network of computers could come from a single computing device that is worn on or in the body. Aside from providing one 24/7 interface to the myriad of computers and sensors that you will have access to, like a good apprentice, this computing device would come to know your personal preferences and sometimes make decisions on your behalf. …………………………………………………………………………………………….…. First there were laptops, then there were netbooks, and now there are "ultrabooks." These mobile devices share several characteristics including the integrated folding design and portability. Differences include size and storage (laptops use hard disks, netbooks rely more heavily on the cloud, and ultrabooks use Flash memory). Despite their similarities and differences, future computer trends point to a lesser reliance on keyboards which could potentially render this category obsolete. Visit any site on the web writing about the future of computers and you will most likely find mention of Moore's Law. Moore's Law is not a strictly adhered to mathematical formula, but a prediction made by Intel's founder co-founder Gordon Moore in 1965. Moore predicted that computing technology would increase in value at the same time itld decrease in cost. More specifically, that innovations in technology would allow a doubling of the 11 number of transistors in a given space every year, the speed of those transistors would increase and manufacturing costs would drop. A computer transistor acts like a small electronic switch. Just like the light switch on your wall, a transistor has only two states, On or Off. A computer interprets this on/off state as a 1 or a 0. Put a whole bunch of these transistors together and you have a computer chip. The central processing unit (CPU) inside your computer probably has around 500 million transistors. Shrinking transistor size not only makes chips smaller, but faster. One benefit of packing transistors closer together is that the electronic pulses take less time to travel between transistors. This can increase the overall speed of the chip. Not everyone agrees that Moore's Law has been accurate throughout the years, (the prediction has changed since its original version), or that it will hold true in the future. But does it really matter? The pace at which computers are doubling their smarts is happening fast enough for me. ……………………………………………………………………………………………………... Apple's iPad has significantly influenced future computer trends. It was soon followed by a flood of tablets. With small sizes, simple designs, extreme portability, Internet access, thousands of apps, and loads of features, tablets can do just about anything a full-size desktop or laptop can do. They fall short in the keyboard arena, but again, that may be about to change. ……………………………………………………………………………………………………... While speech recognition is still imperfect, it has improved greatly in recent years. Windows 7 includes a built-in speech recognition program in its operating system while Nuance's Dragon Naturally Speaking software continues to gain acceptance. Not only is the keyboard in danger, the mouse is too thanks to touchscreen technology. Tablets and smartphones currently make use of touchscreen technology and many "all in one" desktops now come with touchscreen LCDs. When Windows 8 comes out, it is expected to take the touchscreen into the mainstream. By 2020, laboratory experiments are yielding major extensions in the lifespan of mice.* Since rodents and humans share similar DNA, there is now real hope of defeating the aging process. Though a permanent "cure" remains a distant prospect, a number of therapies are already in development which can help to reduce the cell damage, mitochondrial mutations and other adverse effects of growing older.** These can be used as bridges, to buy time for the more dramatic advances in the decades ahead. For those in middle age or younger, the dream of being able to live indefinitely is moving from the realm of science fiction to science fact. This period sees the beginning of major public interest and awareness of the subject. At the same time, however, there is much opposition from religious institutions and conservative groups. 12 Exercise 2 Write your answers to these questions 1. Do you remember when the first primitive computing machines occupied entire buildings? 2. Who is the main inventor of the modern computer? 3. Will future technology change our world? If, yes how will it change? 4. Can you imagine your life without using laptops? 5. Describe all the functions of Apple’s iPad? 6. Can new innovations replace the real world? Exercise 3 Make a list of good and bad points about Future Computers, then discuss these points in pairs, using the expressions from the Function File. Function File a) I’m really like these modern technologies, because… b) What kind of points do you like better…? c) What kind of points do you dislike…? d) What other new innovation items do you invent…? Exercise 4 Complete the description ‘Tablets’ with these words in the correct form. Significantly, access, to be, to follow, tablets, desktop ,laptop, keyboard, simple. Tablets Apple's iPad has _____________influenced future computer trends. It_____ soon __________by a flood of tablets. With_________ small sizes, designs, extreme portability, Internet_______, thousands of apps, and loads of features, _________ can do just about anything a full-size _________or_______ can do. They fall short in the_______ arena, but again, that may be about to change. Exercise 5 Write 10 sentences using these collocations and new vocabulary. Get back, hit back, clean out, express thanks, go about, run in, express an opinion, express horror, empty space, hard time. 2. Theme: Operating System Introduction An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is a vital component of the system software in a computer system. Application programs usually require an operating system to function. 13 Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting for cost allocation of processor time, mass storage, printing, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and will frequently make a system call to an OS function or be interrupted by it. Operating systems can be found on almost any device that contains a computer—from cellular phones and video game consoles to supercomputers and web servers. Examples of popular modern operating systems include Android, BSD, iOS, Linux, Mac OS X, Microsoft Windows, Windows Phone, and IBM z/OS. All these, except Windows and z/OS, share roots in UNIX. 1. Types of operating systems Real-time A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts. Multi-user A multi-user operating system allows multiple users to access a computer system at the same time. Time-sharing systems and Internet servers can be classified as multi-user systems as they enable multiple-user access to a computer through the sharing of time. Single-user operating systems have only one user but may allow multiple programs to run at the same time. Multi-tasking vs. single-tasking A multi-tasking operating system allows more than one program to be running at a time, from the point of view of human time scales. A single-tasking system has only one running program. Multi-tasking can be of two types: pre-emptive or co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions, both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking. Distributed A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system. Embedded Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems. 14 2. History Early computers were built to perform a series of single tasks, like a calculator. Operating systems did not exist in their modern and more complex forms until the early 1960s. Basic operating system features were developed in the 1950s, such as resident monitor functions that could automatically run different programs in succession to speed up processing. Hardware features were added that enabled use of runtime libraries, interrupts, and parallel processing. When personal computers became popular in the 1980s, operating system were made for them similar in concept to those used on larger computers. In the 1940s, the earliest electronic digital systems had no operating systems. Electronic systems of this time were programmed on rows of mechanical switches or by jumper wires on plug boards. These were special-purpose systems that, for example, generated ballistics tables for the military or controlled the printing of payroll checks from data on punched paper cards. After programmable general purpose computers were invented, machine languages (consisting of strings of the binary digits 0 and 1 on punched paper tape) were introduced that sped up the programming process (Stern, 1981). OS/360 was used on most IBM mainframe computers beginning in 1966, including the computers that helped NASA put a man on the moon. In the early 1950s, a computer could execute only one program at a time. Each user had sole use of the computer for a limited period of time and would arrive at a scheduled time with program and data on punched paper cards and/or punched tape. The program would be loaded into the machine, and the machine would be set to work until the program completed or crashed. Programs could generally be debugged via a front panel using toggle switches and panel lights. It is said that Alan Turing was a master of this on the early Manchester Mark 1 machine, and he was already deriving the primitive conception of an operating system from the principles of the Universal Turing machine. Later machines came with libraries of programs, which would be linked to a user's program to assist in operations such as input and output and generating computer code from human-readable symbolic code. This was the genesis of the modern-day computer system. However, machines still ran a single job at a time. At Cambridge University in England the job queue was at one time a washing line from which tapes were hung with different colored clothes-pegs to indicate job-priority. 3. Examples of operating systems Unix was originally written in assembly language. Ken Thompson wrote B, mainly based on BCPL, based on his experience in the MULTICS project. B was replaced by C, and Unix, rewriten in C, developed into a large, complex family of inter-related operating systems which have been influential in every modern operating system. 15 The UNIX-like family is a diverse group of operating systems, with several major subcategories including System V, BSD, and Linux. The name "UNIX" is a trademark of The Open Group which licenses it for use with any operating system that has been shown to conform to their definitions. "UNIX-like" is commonly used to refer to the large set of operating systems which resemble the original UNIX. Unix-like systems run on a wide variety of computer architectures. They are used heavily for servers in business, as well as workstations in academic and engineering environments. Free UNIX variants, such as Linux and BSD, are popular in these areas. Four operating systems are certified by the The Open Group (holder of the Unix trademark) as Unix. HP's HP-UX and IBM's AIX are both descendants of the original System V Unix and are designed to run only on their respective vendor's hardware. In contrast, Sun Microsystems'sSolaris Operating System can run on multiple types of hardware, including x86 and Sparc servers, and PCs. Apple's Mac OS X, a replacement for Apple's earlier (non-Unix) Mac OS, is a hybrid kernel-based BSD variant derived from NeXTSTEP, Mach, and FreeBSD. Unix interoperability was sought by establishing the POSIX standard. The POSIX standard can be applied to any operating system, although it was originally created for various Unix variants. BSD and its descendants The first server for the World Wide Web ran on NeXTSTEP, based on BSD. A subgroup of the Unix family is the Berkeley Software Distribution family, which includes FreeBSD, NetBSD, and OpenBSD. These operating systems are most commonly found on webservers, although they can also function as a personal computer OS. The Internet owes much of its existence to BSD, as many of the protocols now commonly used by computers to connect, send and receive data over a network were widely implemented and refined in BSD. The world wide web was also first demonstrated on a number of computers running an OS based on BSD calledNextStep. BSD has its roots in Unix. In 1974, University of California, Berkeley installed its first Unix system. Over time, students and staff in the computer science department there began adding new programs to make things easier, such as text editors. When Berkely received new VAX computers in 1978 with Unix installed, the school's undergraduates modified Unix even more in order to take advantage of the computer's hardware possibilities. The Defense Advanced Research Projects Agency of the US Department of Defense took interest, and decided to fund the project. Many schools, corporations, and government organizations took notice and started to use Berkeley's version of Unix instead of the official one distributed by AT&T. Steve Jobs, upon leaving Apple Inc. in 1985, formed NeXT Inc., a company that manufactured high-end computers running on a variation of BSD called NeXTSTEP. One of these computers was used by Tim Berners-Lee as the first webserver to create the World Wide Web. 16 Developers like Keith Bostic encouraged the project to replace any non-free code that originated with Bell Labs. Once this was done, however, AT&T sued. Eventually, after two years of legal disputes, the BSD project came out ahead and spawned a number of free derivatives, such as FreeBSD and NetBSD. Mac OS X is a line of open core graphical operating systems developed, marketed, and sold by Apple Inc., the latest of which is pre-loaded on all currently shipping Macintosh computers. Mac OS X is the successor to the original Mac OS, which had been Apple's primary operating system since 1984. Unlike its predecessor, Mac OS X is a UNIX operating system built on technology that had been developed at NeXT through the second half of the 1980s and up until Apple purchased the company in early 1997. The operating system was first released in 1999 as Mac OS X Server 1.0, with a desktop-oriented version (Mac OS X v10.0 "Cheetah") following in March 2001. Since then, six more distinct "client" and "server" editions of Mac OS X have been released, the most recent being OS X 10.8 "Mountain Lion", which was first made available on February 16, 2012 for developers, and was then released to the public on July 25, 2012. Releases of Mac OS X are named after big cats. The server edition, Mac OS X Server, is architecturally identical to its desktop counterpart but usually runs on Apple's line of Macintosh serverhardware. Mac OS X Server includes work group management and administration software tools that provide simplified access to key network services, including a mail transfer agent, a Samba server, an LDAP server, a domain name server, and others. In Mac OS X v10.7 Lion, all server aspects of Mac OS X Server have been integrated into the client version. Linux (or GNU/Linux) is a Unix-like operating system that was developed without any actual Unix code, unlike BSD and its variants. Linux can be used on a wide range of devices from supercomputers to wristwatches. TheLinux kernel is released under an open source license, so anyone can read and modify its code. It has been modified to run on a large variety of electronics. Although estimates suggest that Linux is used on 1.82% of all personal computers, it has been widely adopted for use in servers and embedded systems (such as cell phones). Linux has superseded Unix in most places, and is used on the 10 most powerful supercomputers in the world. The Linux kernel is used in some popular distributions, such as Red Hat,Debian, Ubuntu, Linux Mint and Google's Android. The GNU project is a mass collaboration of programmers who seek to create a completely free and open operating system that was similar to Unix but with completely original code. It was started in 1983 by Richard Stallman, and is responsible for many of the parts of most Linux variants. Thousands of pieces of software for virtually every operating system are licensed under the GNU General Public License. Meanwhile, the Linux kernel began as a side project of Linus Torvalds, a university student from Finland. In 1991, Torvalds began work on it, and posted information about his project on a newsgroup for computer students and programmers. He received a wave of support and volunteers who ended up creating a fullfledged kernel. Programmers from GNU took notice, and members of both projects worked to integrate the finished GNU parts with the Linux kernel in order to create a full-fledged operating system. Chrome is an operating system based on the Linux kernel and designed by Google. Since Chrome OS targets computer users who spend most of their time on the Internet, it is mainly a web browser with no ability to run applications. It relies on Internet applications (or Web apps) used in the web browser to accomplish tasks such as word processing and media viewing, as well as online storage for storing most files. Microsoft Windows is a family of proprietary operating systems designed by Microsoft Corporation and primarily targeted to Intel architecture based computers, with an estimated 88.9 percent total usage share on Web connected computers. The newest version is Windows 8 for workstations and Windows Server 2012 for servers. Windows 7 recently overtook Windows XP as most used OS. 17 Microsoft Windows originated in 1985 as an operating environment running on top of MS-DOS, which was the standard operating system shipped on most Intel architecture personal computers at the time. In 1995, Windows 95 was released which only used MS-DOS as a bootstrap. For backwards compatibility, Win9x could run real-mode MS-DOS and 16 bits Windows 3.x drivers. Windows Me, released in 2000, was the last version in the Win9x family. Later versions have all been based on the Windows NT kernel. Current versions of Windows run on IA-32 and x86-64 microprocessors, although Windows 8 will support ARM architecture. In the past, Windows NT supported non-Intel architectures. Server editions of Windows are widely used. In recent years, Microsoft has expended significant capital in an effort to promote the use of Windows as a server operating system. However, Windows' usage on servers is not as widespread as on personal computers, as Windows competes against Linux and BSD for server market share. There have been many operating systems that were significant in their day but are no longer so, such as AmigaOS; OS/2 from IBM and Microsoft;Mac OS, the non-Unix precursor to Apple's Mac OS X; BeOS; XTS-300; RISC OS; MorphOS and FreeMint. Some are still used in niche markets and continue to be developed as minority platforms for enthusiast communities and specialist applications. OpenVMS formerly from DEC, is still under active development by Hewlett-Packard. Yet other operating systems are used almost exclusively in academia, for operating systems education or to do research on operating system concepts. A typical example of a system that fulfills both roles is MINIX, while for exampleSingularity is used purely for research. Other operating systems have failed to win significant market share, but have introduced innovations that have influenced mainstream operating systems, not least Bell Labs' Plan 9. 4. Components The components of an operating system all exist in order to make the different parts of a computer work together. All user software needs to go through the operating system in order to use any of the hardware, whether it be as simple as a mouse or keyboard or as complex as an Internet component. A kernel connects the application software to the hardware of a computer. With the aid of the firmware and device drivers, the kernel provides the most basic level of control over all of the computer's hardware devices. It manages memory access for programs in the RAM, it determines which programs get access to which hardware resources, it sets up or resets the CPU's operating states for optimal operation at all times, and it organizes the data for long-term non-volatile storage with file systems on such media as disks, tapes, flash memory, etc. The operating system provides an interface between an application program and the computer hardware, so that an application program can interact with the hardware only by obeying rules and procedures programmed into the operating system. The operating system is also a set of services which simplify development and execution of application programs. Executing an application program involves the creation of a process by the operating 18 system kernel which assigns memory space and other resources, establishes a priority for the process in multi-tasking systems, loads program binary code into memory, and initiates execution of the application program which then interacts with the user and with hardware devices. Interrupts are central to operating systems, as they provide an efficient way for the operating system to interact with and react to its environment. The alternative — having the operating system "watch" the various sources of input for events (polling) that require action — can be found in older systems with very small stacks (50 or 60 bytes) but are unusual in modern systems with large stacks. Interrupt-based programming is directly supported by most modern CPUs. Interrupts provide a computer with a way of automatically saving local register contexts, and running specific code in response to events. Even very basic computers support hardware interrupts, and allow the programmer to specify code which may be run when that event takes place. When an interrupt is received, the computer's hardware automatically suspends whatever program is currently running, saves its status, and runs computer code previously associated with the interrupt; this is analogous to placing a bookmark in a book in response to a phone call. In modern operating systems, interrupts are handled by the operating system's kernel. Interrupts may come from either the computer's hardware or from the running program. When a hardware device triggers an interrupt, the operating system's kernel decides how to deal with this event, generally by running some processing code. The amount of code being run depends on the priority of the interrupt (for example: a person usually responds to a smoke detector alarm before answering the phone). The processing of hardware interrupts is a task that is usually delegated to software called device driver, which may be either part of the operating system's kernel, part of another program, or both. Device drivers may then relay information to a running program by various means. A program may also trigger an interrupt to the operating system. If a program wishes to access hardware for example, it may interrupt the operating system's kernel, which causes control to be passed back to the kernel. The kernel will then process the request. If a program wishes additional resources (or wishes to shed resources) such as memory, it will trigger an interrupt to get the kernel's attention. Privilege rings for the x86 available in protected mode. Operating systems determine which processes run in each mode. Modern CPUs support multiple modes of operation. CPUs with this capability use at least two modes: protected mode and supervisor mode. The supervisor mode is used by the operating system's kernel for low level tasks that need unrestricted access to hardware, such as controlling how memory is written and erased, and communication with devices like graphics cards. Protected mode, in contrast, is used for almost everything else. Applications operate within protected mode, and can only use hardware by communicating with the kernel, which controls 19 everything in supervisor mode. CPUs might have other modes similar to protected mode as well, such as the virtual modes in order to emulate older processor types, such as 16-bit processors on a 32-bit one, or 32-bit processors on a 64-bit one. When a computer first starts up, it is automatically running in supervisor mode. The first few programs to run on the computer, being theBIOS or EFI, bootloader, and the operating system have unlimited access to hardware - and this is required because, by definition, initializing a protected environment can only be done outside of one. However, when the operating system passes control to another program, it can place the CPU into protected mode. In protected mode, programs may have access to a more limited set of the CPU's instructions. A user program may leave protected modeonly by triggering an interrupt, causing control to be passed back to the kernel. In this way the operating system can maintain exclusive control over things like access to hardware and memory. The term "protected mode resource" generally refers to one or more CPU registers, which contain information that the running program isn't allowed to alter. Attempts to alter these resources generally causes a switch to supervisor mode, where the operating system can deal with the illegal operation the program was attempting (for example, by killing the program). Among other things, a multiprogramming operating system kernel must be responsible for managing all system memory which is currently in use by programs. This ensures that a program does not interfere with memory already in use by another program. Since programs time share, each program must have independent access to memory. Cooperative memory management, used by many early operating systems, assumes that all programs make voluntary use of the kernel's memory manager, and do not exceed their allocated memory. This system of memory management is almost never seen any more, since programs often contain bugs which can cause them to exceed their allocated memory. If a program fails, it may cause memory used by one or more other programs to be affected or overwritten. Malicious programs or viruses may purposefully alter another program's memory, or may affect the operation of the operating system itself. With cooperative memory management, it takes only one misbehaved program to crash the system. Memory protection enables the kernel to limit a process' access to the computer's memory. Various methods of memory protection exist, including memory segmentation and paging. All methods require some level of hardware support (such as the 80286 MMU), which doesn't exist in all computers. In both segmentation and paging, certain protected mode registers specify to the CPU what memory address it should allow a running program to access. Attempts to access other addresses will trigger an interrupt which will cause the CPU to re-enter supervisor mode, placing the kernel in charge. This is called a segmentation violation or Seg-V for short, and since it is both difficult to assign a meaningful result to such an operation, and because it is usually a sign of a misbehaving program, the kernel will generally resort to terminating the offending program, and will report the error. Windows 3.1-Me had some level of memory protection, but programs could easily circumvent the need to use it. A general protection fault would be produced, indicating a segmentation violation had occurred; however, the system would often crash anyway. The use of virtual memory addressing (such as paging or segmentation) means that the kernel can choose what memory each program may use at any given time, allowing the operating system to use the same memory locations for multiple tasks. If a program tries to access memory that isn't in its current range of accessible memory, but nonetheless has been allocated to it, the kernel will be interrupted in the same way as it would if the program were to exceed its allocated memory. (See section on memory management.) Under UNIX this kind of interrupt is referred to as a page fault. When the kernel detects a page fault it will generally adjust the virtual memory range of the program which triggered it, granting it access to the memory requested. This gives the kernel 20 discretionary power over where a particular application's memory is stored, or even whether or not it has actually been allocated yet. In modern operating systems, memory which is accessed less frequently can be temporarily stored on disk or other media to make that space available for use by other programs. This is called swapping, as an area of memory can be used by multiple programs, and what that memory area contains can be swapped or exchanged on demand. "Virtual memory" provides the programmer or the user with the perception that there is a much larger amount of RAM in the computer than is really there. Multitasking refers to the running of multiple independent computer programs on the same computer; giving the appearance that it is performing the tasks at the same time. Since most computers can do at most one or two things at one time, this is generally done via timesharing, which means that each program uses a share of the computer's time to execute. An operating system kernel contains a piece of software called a scheduler which determines how much time each program will spend executing, and in which order execution control should be passed to programs. Control is passed to a process by the kernel, which allows the program access to the CPU and memory. Later, control is returned to the kernel through some mechanism, so that another program may be allowed to use the CPU. This so-called passing of control between the kernel and applications is called a context switch. An early model which governed the allocation of time to programs was called cooperative multitasking. In this model, when control is passed to a program by the kernel, it may execute for as long as it wants before explicitly returning control to the kernel. This means that a malicious or malfunctioning program may not only prevent any other programs from using the CPU, but it can hang the entire system if it enters an infinite loop. Modern operating systems extend the concepts of application preemption to device drivers and kernel code, so that the operating system has preemptive control over internal runtimes as well. The philosophy governing preemptive multitasking is that of ensuring that all programs are given regular time on the CPU. This implies that all programs must be limited in how much time they are allowed to spend on the CPU without being interrupted. To accomplish this, modern operating system kernels make use of a timed interrupt. A protected mode timer is set by the kernel which triggers a return to supervisor mode after the specified time has elapsed. (See above sections on Interrupts and Dual Mode Operation.) On many single user operating systems cooperative multitasking is perfectly adequate, as home computers generally run a small number of well tested programs. The AmigaOS is an exception, having pre-emptive multitasking from its very first version. Windows NT was the first version of Microsoft Windows which enforced preemptive multitasking, but it didn't reach the home user market until Windows XP (since Windows NT was targeted at professionals). Access to data stored on disks is a central feature of all operating systems. Computers store data on disks using files, which are structured in specific ways in order to allow for faster access, higher reliability, and to make better use out of the drive's available space. The specific way in which files are stored on a disk is called a file system, and enables files to have names and attributes. It also allows them to be stored in a hierarchy of directories or folders arranged in a directory tree. Early operating systems generally supported a single type of disk drive and only one kind of file system. Early file systems were limited in their capacity, speed, and in the kinds of file names and directory structures they could use. These limitations often reflected limitations in the operating systems they were designed for, making it very difficult for an operating system to support more than one file system. While many simpler operating systems support a limited range of options for accessing storage systems, operating systems like UNIX and Linuxsupport a technology known as a virtual file system or VFS. An operating system such as UNIX supports a wide array of storage devices, 21 regardless of their design or file systems, allowing them to be accessed through a common application programming interface (API). This makes it unnecessary for programs to have any knowledge about the device they are accessing. A VFS allows the operating system to provide programs with access to an unlimited number of devices with an infinite variety of file systems installed on them, through the use of specific device driversand file system drivers. A connected storage device, such as a hard drive, is accessed through a device driver. The device driver understands the specific language of the drive and is able to translate that language into a standard language used by the operating system to access all disk drives. On UNIX, this is the language of block devices. When the kernel has an appropriate device driver in place, it can then access the contents of the disk drive in raw format, which may contain one or more file systems. A file system driver is used to translate the commands used to access each specific file system into a standard set of commands that the operating system can use to talk to all file systems. Programs can then deal with these file systems on the basis of filenames, and directories/folders, contained within a hierarchical structure. They can create, delete, open, and close files, as well as gather various information about them, including access permissions, size, free space, and creation and modification dates. Various differences between file systems make supporting all file systems difficult. Allowed characters in file names, case sensitivity, and the presence of various kinds of file attributes makes the implementation of a single interface for every file system a daunting task. Operating systems tend to recommend using (and so support natively) file systems specifically designed for them; for example, NTFS in Windows and ext3 and ReiserFS in Linux. However, in practice, third party drives are usually available to give support for the most widely used file systems in most general-purpose operating systems (for example, NTFS is available in Linux through NTFS-3g, and ext2/3 and ReiserFS are available in Windows through third-party software). Support for file systems is highly varied among modern operating systems, although there are several common file systems which almost all operating systems include support and drivers for. Operating systems vary on file system support and on the disk formats they may be installed on. Under Windows, each file system is usually limited in application to certain media; for example, CDs must use ISO 9660 or UDF, and as of Windows Vista, NTFS is the only file system which the operating system can be installed on. It is possible to install Linux onto many types of file systems. Unlike other operating systems, Linux and UNIX allow any file system to be used regardless of the media it is stored in, whether it is a hard drive, a disc (CD,DVD...), a USB flash drive, or even contained within a file located on another file system. A device driver is a specific type of computer software developed to allow interaction with hardware devices. Typically this constitutes an interface for communicating with the device, through the specific computer bus or communications subsystem that the hardware is connected to, providing commands to and/or receiving data from the device, and on the other end, the requisite interfaces to the operating system and software applications. It is a specialized hardware-dependent computer program which is also operating system specific that enables another program, typically an operating system or applications software package or computer program running under the operating system kernel, to interact transparently with a hardware device, and usually provides the requisite interrupt handling necessary for any necessary asynchronous time-dependent hardware interfacing needs. The key design goal of device drivers is abstraction. Every model of hardware (even within the same class of device) is different. Newer models also are released by manufacturers that provide more reliable or better performance and these newer models are often controlled differently. Computers and their operating systems cannot be expected to know how to control every device, both now and in the future. To solve this problem, operating systems essentially dictate how every type of device should be controlled. The function of the device driver is then to translate these operating system mandated function calls into device specific calls. In theory a 22 new device, which is controlled in a new manner, should function correctly if a suitable driver is available. This new driver will ensure that the device appears to operate as usual from the operating system's point of view. Under versions of Windows before Vista and versions of Linux before 2.6, all driver execution was co-operative, meaning that if a driver entered an infinite loop it would freeze the system. More recent revisions of these operating systems incorporate kernel preemption, where the kernel interrupts the driver to give it tasks, and then separates itself from the process until it receives a response from the device driver, or gives it more tasks to do. Currently most operating systems support a variety of networking protocols, hardware, and applications for using them. This means that computers running dissimilar operating systems can participate in a common network for sharing resources such as computing, files, printers, and scanners using either wired or wireless connections. Networks can essentially allow a computer's operating system to access the resources of a remote computer to support the same functions as it could if those resources were connected directly to the local computer. This includes everything from simple communication, to using networked file systems or even sharing another computer's graphics or sound hardware. Some network services allow the resources of a computer to be accessed transparently, such as SSH which allows networked users direct access to a computer's command line interface. Client/server networking allows a program on a computer, called a client, to connect via a network to another computer, called a server. Servers offer (or host) various services to other network computers and users. These services are usually provided through ports or numbered access points beyond the server's network address. Each port number is usually associated with a maximum of one running program, which is responsible for handling requests to that port. A daemon, being a user program, can in turn access the local hardware resources of that computer by passing requests to the operating system kernel. Many operating systems support one or more vendor-specific or open networking protocols as well, for example, SNA on IBM systems, DECnet on systems from Digital Equipment Corporation, and Microsoft-specific protocols (SMB) on Windows. Specific protocols for specific tasks may also be supported such as NFS for file access. Protocols like ESound, or esd can be easily extended over the network to provide sound from local applications, on a remote system's sound hardware. A computer being secure depends on a number of technologies working properly. A modern operating system provides access to a number of resources, which are available to software running on the system, and to external devices like networks via the kernel. The operating system must be capable of distinguishing between requests which should be allowed to be processed, and others which should not be processed. While some systems may simply distinguish between "privileged" and "non-privileged", systems commonly have a form of requester identity, such as a user name. To establish identity there may be a process of authentication. Often a username must be quoted, and each username may have a password. Other methods of authentication, such as magnetic cards or biometric data, might be used instead. In some cases, especially connections from the network, resources may be accessed with no authentication at all (such as reading files over a network share). Also covered by the concept of requester identity is authorization; the particular services and resources accessible by the requester once logged into a system are tied to either the requester's user account or to the variously configured groups of users to which the requester belongs. In addition to the allow/disallow model of security, a system with a high level of security will also offer auditing options. These would allow tracking of requests for access to resources (such as, "who has been reading this file?"). Internal security, or security from an already running program is only possible if all possibly harmful requests must be carried out through interrupts to the operating system kernel. If programs can directly access hardware and resources, they cannot be secured. 23 External security involves a request from outside the computer, such as a login at a connected console or some kind of network connection. External requests are often passed through device drivers to the operating system's kernel, where they can be passed onto applications, or carried out directly. Security of operating systems has long been a concern because of highly sensitive data held on computers, both of a commercial and military nature. The United States Government Department of Defense (DoD) created the Trusted Computer System Evaluation Criteria (TCSEC) which is a standard that sets basic requirements for assessing the effectiveness of security. This became of vital importance to operating system makers, because the TCSEC was used to evaluate, classify and select trusted operating systems being considered for the processing, storage and retrieval of sensitive or classified information. Network services include offerings such as file sharing, print services, email, web sites, and file transfer protocols (FTP), most of which can have compromised security. At the front line of security are hardware devices known as firewalls or intrusion detection/prevention systems. At the operating system level, there are a number of software firewalls available, as well as intrusion detection/prevention systems. Most modern operating systems include a software firewall, which is enabled by default. A software firewall can be configured to allow or deny network traffic to or from a service or application running on the operating system. Therefore, one can install and be running an insecure service, such as Telnet or FTP, and not have to be threatened by security breach because the firewall would deny all traffic trying to connect to the service on that port. An alternative strategy, and the only sandbox strategy available in systems that do not meet the Popek and Goldberg virtualization requirements, is the operating system not running user programs as native code, but instead either emulates a processor or provides a host for a pcode based system such as Java. Internal security is especially relevant for multi-user systems; it allows each user of the system to have private files that the other users cannot tamper with or read. Internal security is also vital if auditing is to be of any use, since a program can potentially bypass the operating system, inclusive of bypassing auditing. Every computer that is to be operated by an individual requires a user interface. The user interface is usually referred to as a shell and is essential if human interaction is to be supported. The user interface views the directory structure and requests services from the operating system that will acquire data from input hardware devices, such as a keyboard, mouse or credit card reader, and requests operating system services to displayprompts, status messages and such on output hardware devices, such as a video monitor or printer. The two most common forms of a user interface have historically been the command-line interface, where computer commands are typed out line-by-line, and the graphical user interface, where a visual environment (most commonly a WIMP) is present. A screenshot of the KDE Plasma Desktopgraphical user interface. Programs take the form of images on the screen, and the files, folders (directories), and applications take the form of icons and symbols. A mouse is used to navigate the computer. 24 Most of the modern computer systems support graphical user interfaces (GUI), and often include them. In some computer systems, such as the original implementation of Mac OS, the GUI is integrated into the kernel. While technically a graphical user interface is not an operating system service, incorporating support for one into the operating system kernel can allow the GUI to be more responsive by reducing the number of context switches required for the GUI to perform its output functions. Other operating systems are modular, separating the graphics subsystem from the kernel and the Operating System. In the 1980s UNIX, VMS and many others had operating systems that were built this way. Linux and Mac OS X are also built this way. Modern releases of Microsoft Windows such as Windows Vista implement a graphics subsystem that is mostly in user-space; however the graphics drawing routines of versions between Windows NT 4.0 and Windows Server 2003 exist mostly in kernel space. Windows 9x had very little distinction between the interface and the kernel. Many computer operating systems allow the user to install or create any user interface they desire. The X Window System in conjunction withGNOME or KDE Plasma Desktop is a commonly found setup on most Unix and Unix-like (BSD, Linux, Solaris) systems. A number of Windows shell replacements have been released for Microsoft Windows, which offer alternatives to the included Windows shell, but the shell itself cannot be separated from Windows. Numerous Unix-based GUIs have existed over time, most derived from X11. Competition among the various vendors of Unix (HP, IBM, Sun) led to much fragmentation, though an effort to standardize in the 1990s to COSE and CDE failed for various reasons, and were eventually eclipsed by the widespread adoption of GNOME and K Desktop Environment. Prior to free software-based toolkits and desktop environments, Motif was the prevalent toolkit/desktop combination (and was the basis upon which CDE was developed). Graphical user interfaces evolve over time. For example, Windows has modified its user interface almost every time a new major version of Windows is released, and the Mac OS GUI changed dramatically with the introduction of Mac OS X in 1999. A real-time operating system (RTOS) is a multitasking operating system intended for applications with fixed deadlines (real-time computing). Such applications include some small embedded systems, automobile engine controllers, industrial robots, spacecraft, industrial control, and some large-scale computing systems. An early example of a large-scale real-time operating system was Transaction Processing Facility developed by American Airlines and IBM for the Sabre Airline Reservations System. Embedded systems that have fixed deadlines use a real-time operating system suchas VxWorks, PikeOS, eCos, QNX, MontaVista,Linux and RTLinux. Windows CE is a real-time operating system that shares similar APIs to desktop Windows but shares none of desktop Windows' codebase. Symbian OS also has an RTOS kernel (EKA2) starting with version 8.0b. Some embedded systems use operating systems such as Palm OS, BSD, and Linux, although such operating systems do not support real-time computing. Operating system development is one of the most complicated activities in which a computing hobbyist may engage. A hobby operating system may be classified as one whose code has not been directly derived from an existing operating system, and has few users and active developers. http://en.wikipedia.org/wiki/Operating_system - cite_note-25 In some cases, hobby development is in support of a "homebrew" computing device, for example, a simple single-board computer powered by a 6502 microprocessor. Or, development may be for an architecture already in widespread use. Operating system development may come from entirely new concepts, or may commence by modeling an existing operating system. In either case, the hobbyist is his/her own developer, or may interact with a small and sometimes unstructured group of individuals who have like interests. Examples of a hobby operating system include ReactOS and Syllable. 25 Application software is generally written for use on a specific operating system, and sometimes even for specific hardware. When porting the application to run on another OS, the functionality required by that application may be implemented differently by that OS (the names of functions, meaning of arguments, etc.) requiring the application to be adapted, changed, or otherwise maintained. This cost in supporting operating systems diversity can be avoided by instead writing applications against software platforms like Java or Qt. These abstractions have already borne the cost of adaptation to specific operating systems and their system libraries. Another approach is for operating system vendors to adopt standards. For example, POSIX and OS abstraction layers provide commonalities that reduce porting costs. Exercise 1 Draw a line to match the operating system to the correct type of computer. 1. Windows 98 Macintosh 2. System 8 3. Windows 2000 4. Windows 95 PC 5. System 7 Draw a line from the part of the operating system to the place it is stored in a computer. 6. Essential OS - contains programs that the computer needs to run proper Hard Drive 7. Non-essential OS - programs that are important, but not essential to making the computer run. ROM Exercise 2 Vocabulary Worksheet Fill in the blanks with the vocabulary words from the box below. Use each word only one time. Hard drive, user friendly, DOS, Windows, essential, operating system, upgraded, graphics, BIOS, System 8. 1. The large program that controls how the CPU communicates with other hardware components is the__________________. 2. A computer that is easy to operate is called________________. 3. The _______________wakes up the computer and reminds it what to do. 4. The ______________ part of the operating system is stored on ROM. 5. The ______________ part of the operating system is stored on ROM. 6. Important, but non-essential, parts of the operating system are stored on the computer's ____________. 7. Disk-based Operating System is also known as _______________. 8. _____________ is the most common operating system for PCs. 9. Operating systems are constantly being _______________ as technology advances. 10. One example of a Macintosh operating system is ________________. 26 11. A Graphical User Interface uses _______to help the user navigate within the computer system. Exercise 3 Read these questions, then find answers in the text. 1. 2. 3. 4. 5. 6. 7. What types of (OS) do you know? Name them . Had early computers (OS) systems? What Operating Systems’ examples do you know? What are the main components of (OS)? When does the first computer start up to run automatically? What is memory protection? Explain it. What is the difference between the Microsoft Windows and Linux (OS)? Give the extended answer. 8. What is the main aim of the (OS)? 9. What does modern (OS) include? 10. Describe all the processes in the Operating System’s evolution. 11. Give the prominent and the most useful examples of (OS)? Exercise 4 Read the text again, decide if these sentences are true (T) or false (F). Then check your answers. ___ An (OS)is a collection of software that manages computer hardware resources and provides common services for computer programs. ___ (OS) can not be found on almost any device that contains a computer – from cellular phones and video game consoles to sypercomputers and web servers. ___ A multi-user (OS) does not allow multiple users to access a computer system at the same time. ___ When computers in a group work in cooperation, make a distributed system. ___ Embedded (OS) are not designed to be used in embedded computer systems. ___Early computers were built to perform a series of signal tasks, like a calculator. ___ In the 1940s, the earliest electronic digital systems had no (OS). ___ In the 1950s, a computer could execute only two programs at a time. ___ Linex was originally written in assembly language. ___ The Unix – like family is a device group of (OS), with several major sub-categories including System V, BSD, and Linux. Exercise 5 Match the sentences (1-7) with their endings (a-g) to make the statements. 1. 2. 3. 4. 5. 6. 7. ______ ______ ______ ______ ______ ______ ______ Hardware functions such as input and output and memory, Application programs usually A real-time (OS) is a multitasking (OS) Distributed (OS) manages a group of (OS) did not exist in their modern Linux is a Unix – like (OS) that was The newest version is Windows 8 a) _______ independent computers and makes them appear to be a signal computer. b) _______ require an (OS) to function. 27 c) _______ d) _______ e) _______ f) _______ g) _______ that aims at executing real-time applications. and more complex forms until the early 1960s. for workstations and Windows Server 2012 for servers. depended without any actual Unix code, unlike DSD and its variants. the (OS) acts as an intermediately between programs and the computer hardware. Exercise 6 Make sentences by the following words using new vocabulary. Server, to support, the GNU project, to run, application, embed, to base, effort, significant, innovation. Exercise 7 Write short summaries to the following topics. _______ Examples of Operating System _______ Operating System’s History _______ Operating system Componets 3.Theme: Computers’ Development History Computer History and Development Nothing epitomizes modern life better than the computer. For better or worse, computers have infiltrated every aspect of our society. Today computers do much more than simply compute: supermarket scanners calculate our grocery bill while keeping store inventory; computerized telephone switching centers play traffic cop to millions of calls and keep lines of communication untangled; and automatic teller machines (ATM) let us conduct banking transactions from virtually anywhere in the world. But where did all this technology come from and where is it heading? To fully understand and appreciate the impact computers have on our lives and promises they hold for the future, it is important to understand their evolution. 1. Early Computing Machines and Inventors The abacus, which emerged about 5,000 years ago in Asia Minor and is still in use today, may be considered the first computer. This device allows users to make computations using a system of sliding beads arranged on a rack. Early merchants used the abacus to keep trading transactions. But as the use of paper and pencil spread, particularly in Europe, the abacus lost its importance. It took nearly 12 centuries, however, for the next significant advance in computing devices to emerge. In 1642, Blaise Pascal (1623-1662), the 18-year-old son of a French tax collector, invented what he called a numerical wheel calculator to help his father with his duties. This brass rectangular box, also called a Pascaline, used eight movable dials to add sums up to eight figures long. Pascal's device used a base of ten to accomplish this. For example, as one dial moved ten notches, or one complete revolution, it moved the next dial - which represented the ten's column - one place. When the ten's dial moved one revolution, the dial representing the hundred's place moved one notch and so on. The drawback to the Pascaline, of course, was its limitation to addition. 28 In 1694, a German mathematician and philosopher, Gottfried Wilhem von Leibniz (16461716), improved the Pascaline by creating a machine that could also multiply. Like its predecessor, Leibniz's mechanical multiplier worked by a system of gears and dials. Partly by studying Pascal's original notes and drawings, Leibniz was able to refine his machine. The centerpiece of the machine was its stepped-drum gear design, which offered an elongated version of the simple flat gear. It wasn't until 1820, however, that mechanical calculators gained widespread use. Charles Xavier Thomas de Colmar, a Frenchman, invented a machine that could perform the four basic arithmetic functions. Colmar's mechanical calculator, the arithometer, presented a more practical approach to computing because it could add, subtract, multiply and divide. With its enhanced versatility, the arithometer was widely used up until the First World War. Although later inventors refined Colmar's calculator, together with fellow inventors Pascal and Leibniz, he helped define the age of mechanical computation. The real beginnings of computers as we know them today, however, lay with an English mathematics professor, Charles Babbage (1791-1871). Frustrated at the many errors he found while examining calculations for the Royal Astronomical Society, Babbage declared, "I wish to God these calculations had been performed by steam!" With those words, the automation of computers had begun. By 1812, Babbage noticed a natural harmony between machines and mathematics: machines were best at performing tasks repeatedly without mistake; while mathematics, particularly the production of mathematics tables, often required the simple repetition of steps. The problem centered on applying the ability of machines to the needs of mathematics. Babbage's first attempt at solving this problem was in 1822 when he proposed a machine to perform differential equations, called a Difference Engine. Powered by steam and large as a locomotive, the machine would have a stored program and could perform calculations and print the results automatically. After working on the Difference Engine for 10 years, Babbage was suddenly inspired to begin work on the first general-purpose computer, which he called the Analytical Engine. Babbage's assistant, Augusta Ada King, Countess of Lovelace (1815-1842) and daughter of English poet Lord Byron, was instrumental in the machine's design. One of the few people who understood the Engine's design as well as Babbage, she helped revise plans, secure funding from the British government, and communicate the specifics of the Analytical Engine to the public. Also, Lady Lovelace's fine understanding of the machine allowed her to create the instruction routines to be fed into the computer, making her the first female computer programmer. In the 1980's, the U.S. Defense Department named a programming language ADA in her honor. 29 Babbage's steam-powered Engine, although ultimately never constructed, may seem primitive by today's standards. However, it outlined the basic elements of a modern general purpose computer and was a breakthrough concept. Consisting of over 50,000 components, the basic design of the Analytical Engine included input devices in the form of perforated cards containing operating instructions and a "store" for memory of 1,000 numbers of up to 50 decimal digits long. It also contained a "mill" with a control unit that allowed processing instructions in any sequence, and output devices to produce printed results. Babbage borrowed the idea of punch cards to encode the machine's instructions from the Jacquard loom. The loom, produced in 1820 and named after its inventor, Joseph-Marie Jacquard, used punched boards that controlled the patterns to be woven. In 1889, an American inventor, Herman Hollerith (1860-1929), also applied the Jacquard loom concept to computing. His first task was to find a faster way to compute the U.S. census. The previous census in 1880 had taken nearly seven years to count and with an expanding population, the bureau feared it would take 10 years to count the latest census. Unlike Babbage's idea of using perforated cards to instruct the machine, Hollerith's method used cards to store data information which he fed into a machine that compiled the results mechanically. Each punch on a card represented one number, and combinations of two punches represented one letter. As many as 80 variables could be stored on a single card. Instead of ten years, census takers compiled their results in just six weeks with Hollerith's machine. In addition to their speed, the punch cards served as a storage method for data and they helped reduce computational errors. Hollerith brought his punch card reader into the business world, founding Tabulating Machine Company in 1896, later to become International Business Machines (IBM) in 1924 after a series of mergers. Other companies such as Remington Rand and Burroghs also manufactured punch readers for business use. Both business and government used punch cards for data processing until the 1960's. In the ensuing years, several engineers made other significant advances. Vannevar Bush (1890-1974) developed a calculator for solving differential equations in 1931. The machine could solve complex differential equations that had long left scientists and mathematicians baffled. The machine was cumbersome because hundreds of gears and shafts were required to represent numbers and their various relationships to each other. To eliminate this bulkiness, John V. Atanasoff (b. 1903), a professor at Iowa State College (now called Iowa State University) and his graduate student, Clifford Berry, envisioned an all-electronic computer that applied Boolean algebra to computer circuitry. This approach was based on the mid-19th century work of George Boole (1815-1864) who clarified the binary system of algebra, which stated that any mathematical equations could be stated simply as either true or false. By extending this concept to electronic circuits in the form of on or off, Atanasoff and Berry had developed the first allelectronic computer by 1940. Their project, however, lost its funding and their work was overshadowed by similar developments by other scientists. 30 2. Five Generations of Computers First Generation (1945-1956) With the onset of the Second World War, governments sought to develop computers to exploit their potential strategic importance. This increased funding for computer development projects hastened technical progress. By 1941 German engineer Konrad Zuse had developed a computer, the Z3, to design airplanes and missiles. The Allied forces, however, made greater strides in developing powerful computers. In 1943, the British completed a secret code-breaking computer called Colossus to decode German messages. The Colossus's impact on the development of the computer industry was rather limited for two important reasons. First, Colossus was not a general-purpose computer; it was only designed to decode secret messages. Second, the existence of the machine was kept secret until decades after the war. American efforts produced a broader achievement. Howard H. Aiken (1900-1973), a Harvard engineer working with IBM, succeeded in producing an all-electronic calculator by 1944. The purpose of the computer was to create ballistic charts for the U.S It was about half as long as a football field and contained about 500 miles of wiring. The Harvard-IBM Automatic Sequence Controlled Calculator, or Mark I for short, was an electronic relay computer. It used electromagnetic signals to move mechanical parts. The machine was slow (taking 3-5 seconds per calculation) and inflexible (in that sequences of calculations could not change); but it could perform basic arithmetic as well as more complex equations. Numerical Integrator and Computer (ENIAC), produced by a partnership between the U.S. government and the University of Pennsylvania. Consisting of 18,000 vacuum tubes, 70,000 resistors and 5 million soldered joints, the computer was such a massive piece of machinery that it consumed 160 kilowatts of electrical power, enough energy to dim the lights in an entire section of Philadelphia. Developed by John Presper Eckert (1919-1995) and John W. Mauchly (1907-1980), ENIAC, unlike the Colossus and Mark I, was a general-purpose computer that computed at speeds 1,000 times faster than Mark I. 31 In the mid-1940's John von Neumann (1903-1957) joined the University of Pennsylvania team, initiating concepts in computer design that remained central to computer engineering for the next 40 years. Von Neumann designed the Electronic Discrete Variable Automatic Computer (EDVAC) in 1945 with a memory to hold both a stored program as well as data. This "stored memory" technique as well as the "conditional control transfer," that allowed the computer to be stopped at any point and then resumed, allowed for greater versatility in computer programming. The key element to the von Neumann architecture was the central processing unit, which allowed all computer functions to be coordinated through a single source. In 1951, the UNIVAC I (Universal Automatic Computer), built by Remington Rand, became one of the first commercially available computers to take advantage of these advances. Both the U.S. Census Bureau and General Electric owned UNIVACs. One of UNIVAC's impressive early achievements was predicting the winner of the 1952 presidential election, Dwight D. Eisenhower. First generation computers were characterized by the fact that operating instructions were made-to-order for the specific task for which the computer was to be used. Each computer had a different binary-coded program called a machine language that told it how to operate. This made the computer difficult to program and limited its versatility and speed. Other distinctive features of first generation computers were the use of vacuum tubes (responsible for their breathtaking size) and magnetic drums for data storage. Second Generation Computers (1956-1963) By 1948, the invention of the transistor greatly changed the computer's development. The transistor replaced the large, cumbersome vacuum tube in televisions, radios and computers. As a result, the size of electronic machinery has been shrinking ever since. The transistor was at work in the computer by 1956. Coupled with early advances in magnetic-core memory, transistors led to second generation computers that were smaller, faster, more reliable and more energy-efficient than their predecessors. The first large-scale machines to take advantage of this transistor technology were early supercomputers, Stretch by IBM and LARC by Sperry-Rand. These computers, both developed for atomic energy laboratories, could handle an enormous amount of data, a capability much in demand by atomic scientists. The machines were costly, however, and tended to be too powerful for the business sector's computing needs, thereby limiting their attractiveness. Only two LARCs were ever installed: one in the Lawrence Radiation Labs in Livermore, California, for which the computer was named (Livermore Atomic Research Computer) and the other at the U.S. Navy Research and Development Center in Washington, D.C. Second generation computers replaced machine language with assembly language, allowing abbreviated programming codes to replace long, difficult binary codes. Throughout the early 1960's, there were a number of commercially successful second generation computers used in business, universities, and government from companies such as Burroughs, Control Data, Honeywell, IBM, Sperry-Rand, and others. These second generation 32 computers were also of solid state design, and contained transistors in place of vacuum tubes. They also contained all the components we associate with the modern day computer: printers, tape storage, disk storage, memory, operating systems, and stored programs. One important example was the IBM 1401, which was universally accepted throughout industry, and is considered by many to be the Model T of the computer industry. By 1965, most large business routinely processed financial information using second generation computers. It was the stored program and programming language that gave computers the flexibility to finally be cost effective and productive for business use. The stored program concept meant that instructions to run a computer for a specific function (known as a program) were held inside the computer's memory, and could quickly be replaced by a different set of instructions for a different function. A computer could print customer invoices and minutes later design products or calculate paychecks. More sophisticated high-level languages such as COBOL (Common Business-Oriented Language) and FORTRAN (Formula Translator) came into common use during this time, and have expanded to the current day. These languages replaced cryptic binary machine code with words, sentences, and mathematical formulas, making it much easier to program a computer. New types of careers (programmer, analyst, and computer systems expert) and the entire software industry began with second generation computers. Third Generation Computers (1964-1971) Though transistors were clearly an improvement over the vacuum tube, they still generated a great deal of heat, which damaged the computer's sensitive internal parts. The quartz rock eliminated this problem. Jack Kilby, an engineer with Texas Instruments, developed the integrated circuit (IC) in 1958. The IC combined three electronic components onto a small silicon disc, which was made from quartz. Scientists later managed to fit even more components on a single chip, called a semiconductor. As a result, computers became ever smaller as more components were squeezed onto the chip. Another third-generation development included the use of an operating system that allowed machines to run many different programs at once with a central program that monitored and coordinated the computer's memory. Fourth Generation (1971-Present) After the integrated circuits, the only place to go was down - in size, that is. Large scale integration (LSI) could fit hundreds of components onto one chip. By the 1980's, very large scale integration (VLSI) squeezed hundreds of thousands of components onto a chip. Ultra-large scale integration (ULSI) increased that number into the millions. The ability to fit so much onto an area about half the size of a U.S. dime helped diminish the size and price of computers. It also increased their power, efficiency and reliability. The Intel 4004 chip, developed in 1971, took the integrated circuit one step further by locating all the components of a computer (central processing unit, memory, and input and output controls) on a minuscule chip. Whereas previously the integrated circuit had had to be manufactured to fit a special purpose, now one microprocessor could be manufactured and then programmed to meet any number of demands. Soon everyday household items such as microwave ovens, television sets and automobiles with electronic fuel injection incorporated microprocessors. Such condensed power allowed everyday people to harness a computer's power. They were no longer developed exclusively for large business or government contracts. By the mid1970's, computer manufacturers sought to bring computers to general consumers. These minicomputers came complete with user-friendly software packages that offered even nontechnical users an array of applications, most popularly word processing and spreadsheet programs. Pioneers in this field were Commodore, Radio Shack and Apple Computers. In the early 1980's, arcade video games such as Pac Man and home video game systems such as the Atari 2600 ignited consumer interest for more sophisticated, programmable home computers. 33 In 1981, IBM introduced its personal computer (PC) for use in the home, office and schools. The 1980's saw an expansion in computer use in all three arenas as clones of the IBM PC made the personal computer even more affordable. The number of personal computers in use more than doubled from 2 million in 1981 to 5.5 million in 1982. Ten years later, 65 million PCs were being used. Computers continued their trend toward a smaller size, working their way down from desktop to laptop computers (which could fit inside a briefcase) to palmtop (able to fit inside a breast pocket). In direct competition with IBM's PC was Apple's Macintosh line, introduced in 1984. Notable for its user-friendly design, the Macintosh offered an operating system that allowed users to move screen icons instead of typing instructions. Users controlled the screen cursor using a mouse, a device that mimicked the movement of one's hand on the computer screen. As computers became more widespread in the workplace, new ways to harness their potential developed. As smaller computers became more powerful, they could be linked together, or networked, to share memory space, software, information and communicate with each other. As opposed to a mainframe computer, which was one powerful computer that shared time with many terminals for many applications, networked computers allowed individual computers to form electronic co-ops. Using either direct wiring, called a Local Area Network (LAN), or telephone lines, these networks could reach enormous proportions. A global web of computer circuitry, the Internet, for example, links computers worldwide into a single network of information. During the 1992 U.S. presidential election, vice-presidential candidate Al Gore promised to make the development of this so-called "information superhighway" an administrative priority. Though the possibilities envisioned by Gore and others for such a large network are often years (if not decades) away from realization, the most popular use today for computer networks such as the Internet is electronic mail, or E-mail, which allows users to type in a computer address and send messages through networked terminals across the office or across the world. Fifth Generation (Present and Beyond) Defining the fifth generation of computers is somewhat difficult because the field is in its infancy. The most famous example of a fifth generation computer is the fictional HAL9000 from Arthur C. Clarke's novel, 2001: A Space Odyssey. HAL performed all of the functions currently envisioned for real-life fifth generation computers. With artificial intelligence, HAL could reason well enough to hold conversations with its human operators, use visual input, and learn from its own experiences. (Unfortunately, HAL was a little too human and had a psychotic breakdown, commandeering a spaceship and killing most humans on board.) Though the wayward HAL9000 may be far from the reach of real-life computer designers, many of its functions are not. Using recent engineering advances, computers are able to accept spoken word instructions (voice recognition) and imitate human reasoning. The ability to translate a foreign language is also moderately possible with fifth generation computers. This feat seemed a simple objective at first, but appeared much more difficult when programmers realized that human understanding relies as much on context and meaning as it does on the simple translation of words. Many advances in the science of computer design and technology are coming together to enable the creation of fifth-generation computers. Two such engineering advances are parallel processing, which replaces von Neumann's single central processing unit design with a system harnessing the power of many CPUs to work as one. Another advance is superconductor technology, which allows the flow of electricity with little or no resistance, greatly improving the speed of information flow. Computers today have some attributes of fifth generation computers. For example, expert systems assist doctors in making diagnoses by applying the problem-solving steps a doctor might use in assessing a patient's needs. It will take several more years of development before expert systems are in widespread use. 34 Personal Computers History and Development The personal computer (PC) has revolutionized business and personal activities and even the way people talk and think; however, its development has been less of a revolution than an evolution and convergence of three critical elements - thought, hardware, and software. Although the PC traces its lineage to the mainframe and minicomputers of the 1950s and 1960s, the conventional thought that was prevalent during the first thirty years of the computer age saw no value in a small computer that could be used by individuals. A PC is a microcomputer, so named because it is smaller than a minicomputer, which in turn is smaller than a mainframe computer. While early mainframes and their peripheral devices often took up the floor space of a house, minicomputers are about the size of a refrigerator and stove. The microcomputer, whose modern development traces back to the early 1970s, and fits on a desk. From the start, the creation of the computer was centered around the concept that a single unit would be used to perform complex calculations with greater speed and accuracy than humans could achieve. From the beginning, computers baffled the populous with their capability. In corporate and government offices and on university campuses, information processing departments sprouted up to serve the computer. The IBM 701, which was introduced in 1952 as a business computer, was comprised of several units that could be shipped and connected at a customer's location, rather than the earlier massive units that had to be assembled on site. In 1953, IBM began shipping the first mass-produced computer, the IBM 650. IBM introduced the first solidstate (transistorized) computer in 1959, the IBM 7090. Then in 1964, IBM culminated over $1 billion in research when it brought out the System/360 series of computers. Unlike other mainframes, the System/360 computers were compatible with each other. By 1960, the computer was king. Companies hired armies of technicians and programmers to write its operating programs and software, fix it, and allocate the precious computer time. The capability of the machines was more than a mere mortal could fathom, but gathering raw data and "keying" it in so the computer could "crunch the numbers" was a complicated and time-consuming task. Frustrations abounded, computer errors were called "glitches," and the phrases "garbage in/garbage out," "It's a computer mistake," and "Sorry, the computer's down and we can't do anything," were introduced into the lexicon. On college campuses in the 1960s, students carried bundles of computer cards to and from class, hoping that their share of the valuable computer time would not be bumped or allocated to someone else. The term, "Do not fold, spindle or mutilate," was coined so people wouldn't disable the process of feeding the punched computer cards into punch card readers, where the intricate patterns of holes were decoded. The computer mystique was reinforced in people every time they heard of some new accomplishment. In 1961, a computer calculated the value of pi to 100,000 decimal places. A computer could play checkers, and in 1967 a chess playing computer program was made an honorary member of the United States Chess Federation. Banks began printing checks with magnetic ink so they could be processed by the computers. Until 1971, nobody even thought of a computer as anything but a big, fast, electronic brain that resided in a climate-controlled room and consumed data and electricity in massive quantities. In 1971, an Intel 4004 chip containing 4004 transistors was programmed to perform complex mathematical calculations; the hand-held calculator was born. Suddenly, scientists and engineers could carry the computational power of a computer with them to job sites, classrooms, and laboratories; but the hand-held calculator, like the ENIAC before it, was not yet a computer. The microprocessor was developed by Robert Noyce, the founder of Intel and one of the inventors of the integrated circuit, and brought with it a change in the way people worked. 35 Exercise 1 Decide if the sentences are true (T) or false (F). 1. Computers have not infiltrated every aspect of our society. ______ 2. The personal computer (PC) has revolutionized business and personal activities and even the way people talk and think; ______ 3. Defining the fifth generation of computers is somewhat difficult because the field is in its infancy._____ 4. In 1697, a German mathematician and philosopher, Gottfried Wilhem von Leibniz (1646-1716), improved the Pascaline by creating a machine that could also multiply. _____ 5. The real beginnings of computers as we know them today, however, lay with an English naturalist professor, Charles Babbage (1791-1871). ___ 6. In the 1980's, the U.S. Defense Department named a programming language ADA. _____ 7. With the onset of the Second World War, governments sought to develop computers to exploit their potential strategic importance. _____ 8. American efforts produced a broader achievement. _____ 9. In the mid-1940's John von Neumann (1903-1957) joined the University of Pennsylvania team, initiating concepts in computer design that remained central to computer engineering for the next 40 years. ______ 10. By 1958, the invention of the transistor greatly changed the computer's development. ____ Exercise 2 Answer the following questions What was the real computers’ beginning? Who was the first computers’ inventor? When did he invent the first computer? How many variables could be stored on a single card? What was the influence of the Second World War to the computers’ development? What was the computer’s purpose for the U.S. Navy? How many resistors, vacuum tubes and solders joints were in the first computers in the USA? 7. What was the second step in the computers’ development? Give the extended answer. 8. What was the program and programming language like in 1965? 9. What is the integrated circuit and what it’s purpose? 10. Define the fifth generation of computers? 1. 2. 3. 4. 5. 6. Exercise 3 Complete each gap with one word, using the words in the chart. Activities, development, prevalent, revolutionized, elements, evolution, lineage, hardware, minicomputers, age, individuals. Personal Computers History and Development The personal computer (PC) has_____________ business and personal___________ and even the way people talk and think; however, its_________thas been less of a revolution than 36 an________ and convergence of three critical ______-- thought,_______ , and software. Although the PC traces its _______to the mainframe and_______ of the 1950s and 1960s, the conventional thought that was________ during the first thirty years of the computer_______ saw no value in a small computer that could be used by___________. Exercise 4 Write dialogues to the following themes: Computers’ Inventors Five Computers’ Generations Personal Computers’ History and Development New Technologies and Ideas Exercise 5 Give definitions to these words and word combinations Transaction, centerpiece, equation, to calculate, integrated circuit, to solve, electronic circuit, data, computer program, transistor, capability, high-level language, single chip, central processing unit, software, hardware, magnetic ink. 4. Theme: Surf the Net 1. Lead-in Match the words/phrases (1-6) to the definitions (a-f) 2. a) Mark the statements as T (true) or F (false). The Internet was started in 1990. F The Internet links computers.___ To visit a web site, you simply enter the telephone number. ___ The main use of the Internet is to find mistakes.___ Using the Internet is getting more expensive.___ b) Then correct the false statements, as in the example. The Internet wasn’t started in 1990. It was stalled in 1968. 3. Read the information leaflet about the Internet, and match the questions (a-J) to the numbered spaces (1-6), as in the example. Then, explain the words in bold. The Internet: FAQs (Frequently Asked Questions) The Internet is without doubt one of the most important inventions in history. It was started in 1968 by the US government, but at first it was used mainly by scientists. Since 1990, when the World Wide Web was created, it has changed the world, and its uses are growing every day. 37 1 (a)... What exactly is the Internet?............................................................................................. The Internet is a network (several networks, in fact) of millions of computers around the world, connected by phone lines, satellite or cable, so that all the computers on the net can exchange information with each other. 2 ………………………….…………………………………………………………………….. Not quite. The Internet links computers, and the World WideWeb is a system which links the information stored inside these computers. 3 ……………………………………………………………………………….………………… A company or organisation stores its information in electronic documents on one of the Internet computers, somewhere in the world. This computer space - the company’s web site - has an address, in the same way that every telephone has a number. To visit a web site, you simply enter the address. Your computer is connected to the web site, a document is downloaded, and a page appears on your computer screen. 4 ………………………………………………………………………………………………… When you visit a web site looking for information, some words on the page may be underlined, showing that there is more information about the subject in another document. If you click on one of these words, the Web automatically connects your computer to a new document or web site, even if this is stored thousands of kilometers away. You’re surfing the net! 5 …………………………………………………………………..……………………………. The main use of the Internet is to find information - for yours schoolwork or job, or just to find out more about your hobbies, sports or current events. You can also use the Internet to read newspapers and magazines, play games, plan your holiday or buy things from your favourite shop. E-mail makes it possible to send electronic messages anywhere in the world in seconds, and you can use the Internet to ‘chat’ with people and make new friends. 6 …………………………………………………………………..…………........................... If you don’t already use the Internet, all you need to get started is a computer, a modem and a phone line. Using the Internet is getting cheaper and easier all the time. Are you ready to surf the Net? There’s a whole exciting Internet world out there waiting for you! a What exactly is the Internet? b What do I need in order to use the Internet? c How do I “surf the Net”? d That’s the same thing as the Web, isn’t it? e What can I use the Internet for? f What is a web site, and how do I visit one? Vocabulary 1. a) Match the items in the two columns to form phrases, as in the example. b) Read the on-line dialogues and fill in the phrases from above. There is one phrase that you do not need. Wolf > Are you there, Gail? Gail > Hi Wolf — yes I’m here — did you get my 1)……………..…………………………………………………………………………...? Wolf > Yeah, I got it just now. Sorry I didn’t have the chance to check my mail earlier — I was too busy 2)………………………………………………………………………………………… 38 Gail > Did you find any good 3)………….....................................................................................? Wolf > Well, I found a great site called Music Mania. You can 4)……………………………… on all the best groups. You can even download songs and video clips! Flyer > Are you on-line, Aries? Aries > Hi Flyer - what have you been doing? Flyer > I’ve been catching up on 5)…………………………on the net. What about you? Aries > I’ve been doing boring housework. My 6)………..………… ………………was really dirty. At least I can see what you’ re saying now! Flyer > Yuck! Housework! Surfing the net is much more fun, isn’t it? 2. How do you print something from the net? Put the instructions in the correct order. a Wait for the document to be downloaded and the page to appear on your screen. b Decide which part of the document you want to copy. c Click on the print symbol to print your selection. d Enter the address of the web site. e Wait for your computer to be connected to the web site. 3. Cross the odd word out. Give reasons, as in the example. 1 modem, radio, mouse, keyboard (the others are used with computers) 2 go skiing, join a newsgroup, make new friends, listen to music 3 send e-mail, post a letter, make a phone call, download a document 4 but, however, in conclusion, on the other hand 5 advantages, disadvantages, pros, good points Language Development 4. Fill in the words from the list, then make sentences using the completed phrases. web, surf, exchange, computer, change, get, electronic, enter, current, phone, important 1 ............. inventions 7 to the………. address 2 to ……… the world 8 a ……… …….screen 3 ……………….lines 9 to ………………the net 4 to …… information 10 ……………….. events 5 …………documents 11 to…………started 6 a ………… .……site 5. Fill in the correct prepositions, then make sentences using the completed phrases. 1 ……….. doubt; 2 exchange information ………… each other; 3 ………. the world; 4 appear ……….. the screen; 5 …….the page; 6 information ………. sth; 7 to click ………… sth; 8 waiting ……….. sb; 9 stored ……… a computer; 10 find out …….… sth 6. Writing Read the text again, then use the notes below to write about the Internet. 39 Internet Internet = network of computers around the world You need: computer, modem and phone line To surf the Net, you: enter a web site address, connected to the web site, download document, page appears on screen, click on underlined words, connected to new documents/web sites information for schoolwork/job/ You can use it find hobbies/sports/current events, read to: newspapers/magazines, play games, plan holidays, buy things, send electronic messages (e-mail), ‘chat’ with people, make new friends Theme: 5. Grammar: Direct and Indirect Speech • Grammar: Reported Instructions 7. Study the rule and the examples, then say how reported instructions differ from reported questions. 8. Last Monday Jeff had his fifth lesson on how to use the Internet. His instructor gave him some tips. Put the tips into reported speech. 40 1 ………………………………………………………………………. 2………………………………………………………………………. 3………………………………………………………………………. 4………………………………………………………………………. 5.………………………………………………………………………. 6……………………………………………………………………… 9. Rewrite the sentences in reported speech, as in the example. 1. ‘Who sent the e-mail message?’ Sally asked John. Sally asked John who had sent the e-mail message. 2. ‘He has called twice,’ she said. …………………………………………………………………………….. 3. ‘Where does he live?’ Sue asked. …………………………………………………………………………….. 4. ‘He missed the bus’, Claire said. …………………………………………………………………………….. 5. ‘I see you on Monday,’ Bob said to Lyn. …………………………………………………………………………….. 6. ‘I can’t help you,’ Karen said to Mary. …………………………………………………………………………….. 10. Read the e-mail message and answer the questions. Then, turn the reported instructions into direct speech. To: [email protected] From: [email protected] Date: 13.03.2013 Subject: Tom Billings-new offices Dear Frank, Just a quick note to check that I gave Tom Billings the correct instructions concerning the new offices. I told him to make sure there are phone lines in each office. I asked him to order computers for all the offices. I also told him to finish the decorating by next week. Hope I didn’t forget by next week. Karren Briggs 1. Who sent the message? 2. What is it about? 3. Are the layout and style the same as for a letter? Use the prompts below to write questions with question tags, as in the example. - you/spend/a lot of your free time watching videos - you/have got/a lot of fans - your/fan-club web site/be/one of the most - visited web sites on the net - you/not like/playing computer games - you/get engaged to/the singer Dee Brown last month 41 Laura: I’d like to welcome Chris Newton to the studio this morning. Your fans want to know all about what you do in your free time.1) ... You spend a lot of your free time watching videos, don’t you?... Chris: Yes, I do. I prefer the cinema but I get followed by fans everywhere I go now. Laura: 2)………………………………………………………………………………….………… ……………………………………………………………………………………………… Chris: Yes, I have. Sometimes I can’t believe how much mail I get! Laura:3)…………………………….………………….………………………………….……… Chris: Yes, it is. I love reading e-mail from my fans. Laura: 4)………………..……………………………………..……………………………………. Chris: No, that’s not true. I love playing computer games. It’s great fun. Laura: 5)……………………………………….………………………………………………… Chris: I’m sorry. I don’t want to talk about Dee. That’s private. Laura: Oh ... okay. Well, thanks for coming into the studio to talk to us. Now, let’s hear your latest song ... 12. The students in Mr Penny’s class are having a test. Look at his instructions and report them, as in the example. 1 Mr Penny told them not to talk during the test 2 …………………………………………………………………………………………………… 3 …………………………………………………………………………………………………… 4 …………………………………………………………………………………………………… 5 …………………………………………………………………………………………………… 6 …………………………………………………………………………………………………… 7 …………………………………………………………………………………………………… 8 …………………………………………………………………………………………………… 13. Read the reported conversation, then complete the actual conversation using direct speech. 42 I asked Nancy where she lived, and she told me that she lived in Perth, Australia. I also asked her how old she was and she told me that she was thirteen years old. When I asked her if she had any hobbies, she told me that she had a lot of hobbies. She added that she enjoyed swimming, playing volleyball and that she also liked collecting stamps. I told her that I collected stamps too, and that I had over 100 stamps from many different countries. I asked her how many she had and she told me that she had about 220 from all over the world. I asked her if she had many friends and she told me that she did, but only two of them were her best friends. Their names are Amy and Ellen. Jenny: Where do you live? Nancy: I 1) ………………………..……………………………………………... Perth, Australia. Jenny: How 2) ………………………………………………………………………………….... ? Nancy: I 3)……………………………………………. ………………………………………….. Jenny: 4) ………………………………… ………………………………………….any hobbies? Nancy: 5) ……………… hobbies. I 6) ……………...…………………………………………… I also 7) ……...…………………………………………………………………………… Jenny: 8) …………, too! I 9) ……………. ………………………………………..from different countries. How 10) ………………………………………………………………………. ? Nancy: I 11) …………............................................................................... from all over the world. Jenny: 12) …………………………………………………………………………. many friends? Nancy: Yes, 13) ……………. ……………….but 14) …………………. ……………………….. Their names are Amy and Ellen. Writing (a For-and-against Essay) 14. Match the viewpoints in column A to their explanations in column B. Then, read the topic sentences in the box below and decide which a) introduces the main topic, b) introduces points for, c) introduces points against, and d) sums up the topic. A B 1 Computers can do certain tasks much faster A As a result, employers can reduce their than people. workers’ workload and increase their wages. 2 Computers don’t make mistakes. B This could lead to high unemployment. 3 Computers don’t need to be paid for the work C This means that they can do the timethey do. consuming tasks while workers concentrate on other tasks. 4 In many industries, computers may replace D This means that they can’t judge people’s people altogether. characters or help people with emotional problems. 5 Computers do not have personalities or E Therefore they can be used to help workers feelings. such as air- traffic controllers or surgeons whose work is dangerous or demanding. Topic Sentences 1On the other hand, using computers in the workplace also has disadvantages. 2 In the last few years computers have become a part of almost everybody’s everyday lives — especially in the workplace. 3 In conclusion, I believe that using computers in the workplace has both positive and negative points. 4 Using computers in the workplace offers many advantages. 43 15 Use the information from Ex. 14 to write a for-and-against essay entitled “The Advantages and Disadvantages of Computers in the Workplace” (100 - 160 words). Use the article in Ex. 13 as a model. 6.Theme: The Web In this theme you will read a factfile, a questionnaire and a web page listen to a survey; take phone messages talk about the Internet; practise making phone calls write a page for the Internet learn more about conditional sentences Warm-up 1 Use the Mini-dictionary to complete the factfile below with the Key Words. KEYWORDS: bookmarks, browser, download, favourites, Internet, links, online, search engine, website, World Wide Web 2. Work in pairs. Are these statements true (T) or false (F)? 1 ___ There are more Internet users in Europe than in North America. 2 ___ Americans send more than four billion emails every year. 3 ___ Search engines like Google can find hundreds of thousands of websites in less than a second. 4 ____ In 2000, over nine million people watched one of Madonna's concerts 'live' on the Internet. 5 ___ Computers operate better when they are cool because they conduct electricity more efficiently. 3. Work in pairs. Write what you have tried or would like to try on the Internet. Example I'd tike to send emails to my cousins in the USA. chat online send emails find information for your studies find information about entertainment/travel listen to and/or download music shop, e.g. for videos, CDs, clothes read about your interests practise your English FACTFILE: The Internet The 1 __________ is an international network of computers – it includes electronic mail (email), the World Wide Web (www), discussion groups and online chatting. To go 2 _________ , you need a 3 ___________, such as Netscape Navigator or Microsoft Internet Explorer. These programs let you see web pages and 4 ___________ information onto your computer. The 5 __________ is a collection of web pages. Each page has6 __________ to other pages which you can get by clicking on words or pictures. A 7 _________ , or web page, is a document available on the World Wide Web. To look for information, type key words into a 8 __________ , such as Google, which gives you a list of useful websites. If you find a good website, you can save it for future reference - put it in your 9 ________ or 10 __________ . 44 Online Before you start 1. Match the Key Words with the things (1-5) in the photo. KEY WORDS: sources of information a CD-ROM encyclopedia, a dictionary, an encyclopedia, the Internet, a reference book on a special topic 2 What problems can people have when they look for information on the Net? What problems have you had? 3 Answer the questionnaire. Are You An Online Student? Your English group is doing a project on Native American folk dancing in Alaska. You have to prepare an article. So ... 1. Do you try to find information: ___ a) on the Internet? b) in an encyclopedia? c) from other reference books? 2. You have about 15 minutes before the end of the lesson. Do you: ___ a) go to the school library to find some information? b) make a list of questions you want to find answers to? c) write down what you already know? 3. You want to start looking for information on the Internet using a search engine (like Google). What key words do you type in and search for? ___ a) Native Americans b) folk dances Alaska c) folk dances 4. You find a really good website. Do you: ___ a) try to remember the address? b) write the address in your notebook? c) put it in your bookmarks or favourites? 5. You find a website with the answer to your dreams a short article called 'Native American folk dances in Alaska'. Do you: ___ a) try to write a summary of the article in your own words? b) print it out and use it to answer the questions on your list? c) copy it, put your name at the top and give it to your teacher? 6.Warm-up Find 14 words related to the Internet. w e b s і t e f a o і o e w x m e d r с h a t r a z u 1 m с r к e і с t d o d с o n l 1 n n o с r к e b b o o к f a v o u y m r w y b h l e n і s i d te e w r n e t) n o t w e n r l n o e a d w j o a r і t e h n l g і n n e к t s t d j w os o r e d к s e s 45 e b e a s і n e l с b o r m o p w s u t e e r r 7.Write example sentences in your notebook with the words from Exercise 6. The Internet is яп international computer network. I use the Internet three times a week.. _____________________________________________________________________________ _____________________________________________________________________________ _____________________________________________________________________________ 7. Theme: Grammar: First and Second Conditional Presentation 1. Read the sentences (1-4) and complete the table with the tenses used. What does'd stand for in sentences 2 and 3? 1. If I didn't use the Net, I wouldn't find information for most of my school projects. 2. If I knew anything about folk dancing, I'd write it all down. 3. If there were only fifteen minutes left, I'd write a list of questions. 4. If I copied it, I'm sure the teacher would know. Condition Consequence if + ________ ____________ 2. Read the sentences in Exercise 1 again. What is he talking about? a situations that are real or will probably happen b imaginary or unlikely situations Complete the rule with two of these words: present, past, future We use the Second Conditional to talk about_________ situations that are unlikely or__________ situations that are imaginary or unreal. Practice 3. Who could say these things? Choose a or b. 1 If I had the money, I would go on holiday to the Caribbean. a a student b a millionaire 2 If I lived in London, I could visit the Science Museum every month. a a Londoner b a New Yorker 4. Use the cues below to write Second Conditional sentences. Example 1 If I didn't have a computer, I wouldn't use the Internet. 1 if/not have computer/not use the Internet 2 if/win lottery/buy a new computer 3 if/play computer games/not be a good student 4 go to Tibet/if/have money 5 if/be a computer expert/earn a lot of money 6 make new friends/if/use Internet 5. Write sentences using the Second Conditional based on these imaginary present situations. Example 1 If I didn't like cooking, I wouldn't work as a chef in a restaurant. 1 I like cooking so I work as a chef in a restaurant. If___________________________________________ 2 I don't think I'll win the race so I probably won't get the prize. If___________________________________________ 46 3 There is very little time left so we can't go on foot. If___________________________________________ 4 I'm very tall so I play in the school basketball team. If______________________________________ 5 Imagine we go on an expedition to Mount Everest - everyone will admire us. If___________________________________________ 6. Which place in the world would you like to go to? Write a Second Conditional sentence about the places below and three other places of your choice. Example If I went to the Grand Canyon, I would take a canoe trip down the Colorado River. •Grand Canyon • Paris • China • New York• the Amazon jungle • Hollywood 7. Imagine what would happen if these things came true. Make two or three conditional sentences for each situation. Example 1 If all the telephone lines in the world went dead, companies would lose a lot of money. People wouldn't be able to call the emergency services. I would miss talking to my friends on the phone. 1 All the telephone lines in the world go dead. 2 There is no Internet. 3 All the computers in the world break down. 4 Everybody speaks the same language. 5 You don't have to go to school. 6 Someone invents a time machine. 8 SECOND CONDITIONAL Second Conditional for present situations that are not real. Write possible sentences using the table. If I had the money, I would buy on a world tour. If I was President of my country, I wouldn't go school holidays longer. make a big car. live school holidays shorter. have here. in the Caribbean. to the Caribbean. more jobs for people. more festivals. 1 If I was President of my country, I would make school holidays longer 2_______________________________________________________________________ 3_______________________________________________________________________ 4_______________________________________________________________________ 5_______________________________________________________________________ 6_______________________________________________________________________ 7_______________________________________________________________________ 8_______________________________________________________________________ 47 Now finish these sentences in any way you want. If I was President of my country,____________________________________________________ ________________________________________________________________________ if I had more money,_______________________________________________________________ _______________________________________________________________________________ Write sentences. Use the Second Conditional. 1. if/not be/any television/people/talk more if there wasn’t any television, people would talk, more. 2 if/I/live in the USA/I/not live/in one of the big cities ________________________________________________________________________ 3 if/it/snow/every day in winter/I/go skiing/as often as possible ________________________________________________________________________ 4 I/visit/the Great Wall/if/I/go/to China ________________________________________________________________________ 5 If/I/become famous/I/not move/to a bigger house ________________________________________________________________________ 6 We/not be happy/if/we/not have/any friends First and Second Conditional. Match the sentence beginning 1-8 with the ends (a-h) 1 If I see Mark, 2 If they have enough money next month, 3 If I watched a horror film on my own at night, 4 If we go out for a meal, 5 If I have a coffee before I go to bed, 6 If they had more money, 7 If we went to that restaurant, 8 If you phoned Simon, a I wouldn't be able to sleep after. b they would buy a new car. c I'll tell him you phoned. d what would you say to him? e we'll go to the new Italian restaurant. f I'd have pasta or pizza. I love them both! g they'll go on holiday to China. h I won't be able to sleep, I'll be wide awake. 1 c 2 ___ 3 ___ 4 ___5 ___ 6 ___ 7 ___ 8 ___ First or Second Conditional? Write sentences with the correct form of the verbs. Use the First or Second conditional. 1. I live in Scotland. If I lived (live) in France, I would learn (learn) French. 2. If I _____ (be) you, I _______ (not go) to the party. I really don't think it's a good idea. 3. I usually see John in the afternoon. I __________ (give) him your message if I____ (see) him later. 4. Don't worry. I __________(help) you with your chemistry homework if you ________(not understand) it. I'm good at chemistry. 5. I _______(buy) a new computer if I ________ (have) enough money. Unfortunately I've only got 50! 6. I'm saving up at the moment. If I_______ (have) enough money at the end of the year, I (buy) a CD player. 48 7. The weather's been very good recently. If it ________ (be) good at the weekend, we (go) to the mountains. 8. I _______ (do) more sport if I ________ (have) more free time, but I'm extremely busy at the moment. Write a First Conditional and a Second Conditional sentence about each subject. Computers 1. do homework on the computer/quicker If you do your homework on the computer, it will be quicker_____________________________ _____________________________________________________________________________ 2. life very different/not have computers Life would be very different if we didn’t have computers.______________________________ _____________________________________________________________________________ Football 3. like football/enjoy watching my team _____________________________________________________________________________ _____________________________________________________________________________ 4. Scotland win the World Cup/be very happy _____________________________________________________________________________ _____________________________________________________________________________ Jobs 5. work hard at school/get good job _____________________________________________________________________________ _____________________________________________________________________________ 6. not be a doctor/like to be a teacher _____________________________________________________________________________ _____________________________________________________________________________ 9. Personalisation. Imagine your ideal future life. Think about your home, job, partner, family, etc. Write conditional sentences to explain why you would like this kind of life. Example I'd like to live in Africa and work as a doctor. If I was a doctor in Africa, I would help a lot of people. 10. In pairs, write your choices. Example I'd like to be an astronaut, because if I were an astronaut, I would... 11. Translate the following sentences into Ukrainian. Pay attention into sequence of tenses. 1. I thought that he finished his work at five every day. 2. I thought that he had finished his work. 3. She supposed that they always came in time. 4. She supposed that they had come in time. 5. He hoped that she studied well. 6. He hoped that she had studied well at school. 7. We knew that he .was ill. 8. We knew that he had been ill. 9. I did not know when they left home. 10. I did not know when they had left home. 11. He said his father was a pilot. 12. He said his father had been a pilot. 13. They were sure she wrote letters to her granny. 49 14. They were sure she had written a letter to her granny. 15. She said that she would visit us in a week. 16. Our teacher said we would be writing the test at two o’clock. 12. Put these sentences in the Past Simple. Pay attention into the changes in the subordinate clause. 1. She says she likes roses. 2. She says he has already written the article. 3. They say they will come to see us next Friday. 4. She says she is glad to see me. 5. We do not know when he comes home. 6. Ann is sure we will arrive on Friday. 7. Peter thinks his friend has just returned home. 8. My teacher believes I will succeed in my studying. 9. I know he always gets up early. 10. We expect Dorothy will join us in the evening. 11. He says he has left his bicycle in the yard. 12. I suppose they met in the street. 13. Put these sentences in the Past Simple. Pay attention into the changes in the subordinate clause. 1. Christy says he will tell you the truth. 2. Nobody knows what she means. 3. We think that he is joking. 4. John says he knows how I feel. 1 5. Harry doesn’t know when his cousin will come. 6. I can’t believe she has done it. 7. He thinks they are driving to the country. 8. She is sure^ we will be glad to meet her. 9. I don’t know where she is. 10. I don’t think they will be having breakfast so early. 11. We hope they have noticed us.' 12. He doesn’t suppose she speaks so much. 13. She says she will let me know when they come. 14. I think he came in a taxi. 15. They are sure we will be waiting for them in the bar. 14. Open the brackets using the sequence of tenses. 1. She realized that nobody (will come/would come). 2. We understood that she (sees/saw) nothing. 3. He said he (will arrive/would arrive) in some days. 4. My mother was sure I already (have come/had come). 5. I didn’t know they (are/were) in the room. 6. We supposed the rain (will stop/would stop) in some hours; 7. He said he never (has been/had been) to Kyiv. 8. We wanted to know who (is singing/was singing) in the next room. 9. I always thought he (is/was) a brave man. 10. When I saw him, he (is working/was working). 11. We know she always (comes/came) in time. 12. They thought he (will have finished/would have finished) his work by the evening. 13. She said she (has/had) a terrible headache. 14. We supposed they (will send/would send) us the documents. 50 15. He said he (has not seen/had not seen) us for ages. 15. Open the brackets using the sequence of tenses. 1. Her brother said he never (to see) this film before. ; 2. He came home and listened: his son (to play) the piano. 3. They didn’t worry too much because they (to lock) the door. 4. I asked her when she (to give) me this book to read. 5. We wanted to know if they (to enjoy) the meal. 6. She supposed she (to like) the hotel. 7. 7.1 am afraid they (not to come) yet. 8. He wanted to know if the station (to be) away. 9. Eric doesn’t know who (to phone) him at five o’clock. 10. He admitted he {not to be) here for weeks. 11. She apologies she (to arrive) so late. 12. Jean promised she never (to speak) to me again. 13. Andy said he just (to buy) a new car. 14. My mother decided that she never (to drink) coffee late at night. 15. I hear you already (to find) a new job. 16. We were sure our children (to sleep). 17. I didn’t think they still (to discuss) this problem. 18. It is remarkable that you (to come) at last. 19. My doctor thinks I (to be) allergic to pineapples. 20. Sophia knew her aunt (to be) glad to visit her in two days. 16. Open the brackets using the sequence of tenses. 1. When I opened the window, I saw the sun (to shine). 2. We are sure Simon (to marry) her some time later. 3. He can’t remember where he (to put) his glasses. 4. George thought the restaurant (to be) expensive. 5. She was disappointed that she (not to get) the job. 6. I didn’t understand why they (to destroy) their relationship. 7. He is not sure they (to find) their way in the darkness. 8. Jane asked me if I (to invite) Ann to the party. 9. People say that he always (to be) very rich. 10. She said she (to wait) for me since seven o’clock. 11. They thought I (to give) them my telephone number. 12. I am afraid I (not can) answer you question. 13. We wanted to know what (to happen) to John. 14. George thought he (can) repair the car himself., 15. She is very upset: she (to break) her watch, r 16. Bill said he (to feel) ill. H: 17. We thought she still (to be) in hospital. 18. I knew he (to pass) his examination at that time. 19. My cousin promised he (to visit) me in a week. 20. We didn’t know they (to be) tired. 17. Translate into English. Pat attention into sequence of tenses. 1. Я думав, що вона хворіє. 2. Ми сподівались, що він прийде вчасно. 3. Я не знав, що його сестра вивчає англійську мову. 4. Він впевнений, що закінчить роботу до вечора. 5. Вона сказала, що не хоче йти на прогулянку. 51 6. Ми хотіли знати, коли вона прийшла. 7. Мій друг каже, що вже прочитав цю статтю.. 8. Я не знав, що він зайнятий і не може мені допомогти. 9. Ніхто не хотів вірити, що він сказав правду. 10. Вона сподівається, що я не працюватиму в неділю. 11. Ми побачили, що діти грають у футбол. 12. Він сказав, що його мати лікар. 18. Form from these sentences complex object sentences. 1. They are working in the garden. (We were sure). 2. I have never been to Paris. (I told). 3. They have been waiting for him for ten minutes. (He didn’t know). 4. Tim hasn’t written for them for ages. (She knew). 5. Kath will not see us. (My mother wrote). 6. He is going to the park. (He told me). 7. They are skating. (I supposed). 8. Somebody has stolen his purse. (He did not notice). 9. Sophie is a very clever girl. (Everybody knew). 10. He doesn’t agree. (He told). 11. She haven’t done her homework. (She said). 12. I don’t like going to parties. (I told them). 13. She doesn’t know how much "the dress cost. (Mary told me). 14. We will come again next year. (We wrote them). 15. I am washing the car. (I told him). 16. He has already seen this play. (He didn’t tell us). 17. She is not feeling very well. (She told the doctor). 18. He is translating the article. (I saw). 19. She will talk to Susan. (She promised). 20. He can not swim. (I didn’t suppose). 19. Translate into English using sequence of tenses. 1. Вона сказала, що буде рада побачити нас знов. 2. Він сказав, що знає, як я себе почуваю. 3. Я сказав, що він щойно повернувся з відрядження. 4. Ми не помітили, як діти вийшли з кімнати. 5. Вона пообіцяла, що надішле нам листівку. 6. Він не хотів вірити, що вони не розуміють його. 7. Він не сказав, що не любить ходити в театр. 8. Ми сподівались, що він уже повернувся додому. 9. Вона сказала, що живе в Києві уже двадцять років. 10. Мій брат сказав, що не згодний зі мною. 11. Ми хотіли знати, де він і що він робить в цей час. 12. Всі знали, що вона поїде у відрядження, але не знали коли вона повернеться. 13. Я не міг зрозуміти, чому він не прийшов. Я подумав, що він хворий. 14. Мама сказала, що вона повернеться до сьомої вечора. 15. Ніхто з учнів не знав, що він такий сильний. 16. Він сказав, що зайнятий, що він працює над доповіддю. 17. Моя сестра сказала, що ніколи не зустрічала цієї жінки раніше і нічого про неї не чула. 18. Ми були дуже раді, що вони не заблудилися в незнайомому місці і прийшли вчасно. 19. Всі думали, що лекція почнеться о десятій. 52 20. Ми не сподівались, що побачимо його знову. 20. Translate into English using sequence of tenses. 1. Він сподівався, що проведе наступне літо біля моря. 2. Мама сказала, що вона хоче залишитись дома. 3. Я знав, що нічого особливого з ним не трапилось. 4. Нам здавалось, що вона сміється над нами. 5. Всі розуміли, що він помиляється, але ніхто не наважувався сказати йому про це. 6. Вона сказала, що чекає свою подругу вже чверть години. 7. Вони спитали мене, що я робитиму в неділю. 8. Я не був впевнений в тому, що він поговорив з батьками. 9. Тренер пояснив нам, що це дуже небезпечний вид спорту. 10. Моя двоюрідна сестра пообіцяла мені, що прийде до мене в гості через тиждень. 11. Батько сказав, що не знає чи дзвонив мені хто- небудь, тому що,його не було вдома. 12. Вона сказала, що не хоче кави, що вона поп’є чаю. 13. Він сповістив нам, що делегація прибуде сюди приблизно о третій. 14. Я хотів знати, які мови вони вивчають і чи розмовляють вони англійською мовою. 15. Він зрозумів, що втратив гарну нагоду заробити трохи грошей. 16. Вона хвилювалась, тому що не знала, чи сподобаються дітям її подарунки. 17. Вони сказали, що економічна ситуація гірша, ніж вони припускали. 18. Ми сподівались, що це буде найцікавіша зустріч. 19. Мій брат написав мені, що він вступив до університету. 53 Література 1. Mark Ibbotson – Professional English in Use, Cambridge University Press, 2009. – 144 с. 2. Dinos Demetriades, Information Technology, Oxford University Press, 2012. – 39 c. Longman, 2006. - 144 с. 3. Kathy Gude with Gayne Wildman – Matrix Intermediate Student′s Book Oxford University Press, 2008. – 152 с. 4. 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Michael Swan How English Works (a grammar practice book), Oxford University Press, 2007. – 358 c.. 16. Lilo Zsolnay USA Country Studies, Lutsk, 1998. – 135 c. 17. Mark Ibbotson, Professional English in Use, Cambridge University Press, 2011. – 166 c. 18. Harris Michael, David Mower – New Opportunities-Intermediate Longman, 2010. - 144с. 19. Баранцев К. Т. Англо-український фразеологічний словник. – Київ: Знання, 2009. 1056 с. 20. Князєва І. О. Граматичний практикум. – Київ: Ранок, 2008. – 35 с. 21. Мансі Є. О. Практикум з англійської мови. - Київ: ВП Логос, 2008. – 159 с. 22. Богатський І. С, Дюканова Н. М. Бізнес-курс англійської мови. – Київ: ВП Логос, 2007. - 349 с. 23. Байбакова І. М. Getting into English. – Львів: Бескид Біт, 2008. – 251 с. 24. Бичкова Н. І. Англійська мова. Комунікативний аспект. – Київ: Либідь, 2009. - 325с. 25. Романов Д. О. Сучасний англо-український словник-довідник. – Донецьк: Бао, 2007. 573 с. 26. Зубков М. В. Великий англо-український словник. – Харків: Фоліо, 2006. - 787 с. 27. Погарська Т. В. Англійська мова. – Харків: Ранок, 2006. - 174с. 28. Шишків А. О. Англо-український тлумачний словник енциклопедичної «лексики». Київ: Києво-Могилянська академія, 2004. - 429с. 29. Богатський І. С, Дюканова Н. М. Бізнес-курс англійської мови. – Київ: ВП Логос – Н, 2007. - 349с. 30 .Мисик Л. О. English Communicative Aspect. – Львів: Світ, 2007. - 430 с. 31. Байбакова І. М. Getting into English. - Львів: Бескид Біт, 2008. – 251 с. 54 NOTES _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ 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_____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ 55 Навчально-методичне видання Іноземна мова (за професійним спрямуванням) Методичні рекомендації до виконання самостійної роботи для студентів ІІІ курсу спеціальності 5.0501201 «ОБСЛУГОВУВАННЯ КОМП’ЮТЕРНИХ СИСТЕМ І МЕРЕЖ» денної форми навчання. Комп’ютерний набір і верстка: Редактор: Семенюк Я.О. Гордіюк О.С. Підписано по друку ________________ 2013. Форма 60х84/16. Папір офіс. Гарн. Таймс. Ум. друк. арк. 3,26 Обл.-вид. арк. 3,0 Тираж 100 прим. Зам.141 Редакційно-видавничий відділ Луцького національного технічного університету 43018 м. Луцьк, вул.. Львівська 75 Друк – РВВ ЛНТУ 56