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INFORMATION TECHNOLOGY FUNDAMENTALS Lecture One Essential Computer Concepts IT Fundamentals 1 Class Website www.blackdecimal.com http://blackdecimal.com/category/infotech IT Fundamentals 2 Course Textbook - Recommended IT Fundamentals 3 Session Objectives • Compare the types of computers • Describe the components of a computer system • Examine data representation and the ASCII code • Learn about processing hardware • Define memory and storage • Describe input and output peripheral devices • Discuss the types of system software and their functions IT Fundamentals 4 LEARNING ABOUT THE COMPONENTS OF COMPUTER SYSTEMS IT Fundamentals 5 What Is a Computer? A computer is an electronic device, operating under the control of instructions stored in its own memory, that can accept data, process the data according to specified rules, produce results, and store the results for future use. Computer is an electronic device that accepts inputs from a user, manipulates the inputs according to the instructions, displays the output and stores the information for retrieval later. IT Fundamentals 6 Data Vrs Information Data is a collection of unprocessed items, which can include text, numbers, images, audio, and video. Information conveys meaning and is useful to people. IT Fundamentals 7 VISUAL OVERVIEW The motherboard and the microprocessor, the hard disk, and the cards that expand the capabilities of the motherboard are inside the tower in a desktop computer. The monitor is the device that displays the output from a computer. The keyboard is the most frequently used input device The most popular pointing device for a desktop computer is a mouse. IT Fundamentals 8 Types of Computers • Personal computers (PCs) are computers typically used by one person in a home or office. • A PC is used for general computing tasks such as word processing, manipulating numbers, working with photographs or graphics, exchanging email, and accessing the Internet. • Examples are desktop computer, a notebook, computer, a tablet PC, or a handheld computers. IT Fundamentals 9 Laptop computer Desktop computer Smartphone Netbook Tablet PC IT Fundamentals 10 • Mainframe computers are typically used by larger businesses and government agencies to centrally store, process, and manage large amounts of data. • Supercomputers are the largest and fastest types computers, they were first developed for high-volume computing tasks such as weather prediction. They are also used by large corporations and government agencies when the tremendous volume of data would seriously delay processing on a mainframe computer. IT Fundamentals 11 A mainframe computer A supercomputer IT Fundamentals 12 Computer Systems • A computer system includes computer hardware and software. • Hardware refers to the physical components of a computer. • Software refers to the intangible components of a computer system, particularly the programs, or lists of instructions, the computer needs to perform a specific task. • Architecture or configuration. - The design and construction of the hardware of a particular computer. IT Fundamentals 13 Data Representation • Data refers to the words, numbers, figures, sounds, and graphics that describe people, events, things, and ideas. • a computer represents “on” with a 1 and “off” with a 0. These numbers are referred to as binary digits, or bits. • A series of eight bits is called a byte • A kilobyte (KB or simply K) is 1024 bytes, or approximately one thousand bytes IT Fundamentals 14 • megabyte (MB) is 1,048,576 bytes, or about one million bytes; • a gigabyte (GB) is 1,073,741,824 bytes, or about one billion bytes; • and a terabyte (TB) is 1024 GB, or approximately one trillion bytes. • The symbols KB, MB, GB, and TB refer to processing capacity, storage capacity, and file sizes. IT Fundamentals 15 Personal computers commonly use the ASCII code to represent character data. • ASCII (pronounced “ASK-ee”) stands for American Standard Code for Information Interchange. • The ASCII system translates the decimal numbers 0–255 into binary data. • Computers translate ASCII into binary data so that they can process it. IT Fundamentals 16 Computers that run the Windows operating systems use the set of Extended ASCII definitions defined by the American National Standards Institute (ANSI) Character ASCII Code ASCII Code Binary Number (space) 32 00100000 $ 36 00100100 A 65 01000001 a 97 01100001 ? 129 10000001 é 233 11101001 IT Fundamentals 17 Processing Hardware • The hardware and the software of a computer system work together to process data and commands. • Modifying data is called processing. • Commands are instructions to the computer on how to process the data. • For example, you issue a command in the word processing program to instruct the computer to center the title in a report. IT Fundamentals 18 Motherboard The motherboard is a circuit board, which is a rigid piece of insulating material with circuits, or electrical paths, on it that control specific functions. IT Fundamentals 19 Microprocessor • Microprocessor is also called the processor or the central processing unit (CPU) • It consists of transistors and electronic circuits on a silicon chip (an integrated circuit embedded in semiconductor material). • The processor is mounted on the motherboard and is responsible for executing instructions to process data. • The speed of the microprocessor determines how fast a computer processes data and executes instructions. IT Fundamentals 20 Microprocessor Microprocessor (front and back views) IT Fundamentals 21 Cards • Cards are removable circuit boards that are inserted into slots on the motherboard to expand the capabilities of the motherboard. • A sound card, for example, translates the digital audio information from the computer into analog sounds that the human ear can hear. IT Fundamentals 22 Types of Memory and Storage MEMORY AND STORAGE IT Fundamentals 23 Memory • Random access memory (RAM) consists of chips on cards that plug into the motherboard, temporarily holds programs and data while the computer is on, and allows the computer to access that information randomly. • RAM is considered volatile memory or temporary memory because it constantly changes while the computer is on and clears when the computer is turned off IT Fundamentals 24 • Cache memory, sometimes called RAM cache or CPU cache, is a special, high-speed memory chip on the motherboard or CPU. • Because the computer can access cache memory more quickly than RAM, frequently and recently accessed data and commands are stored there instead of in RAM. IT Fundamentals 25 • Virtual memory is space on the computer’s storage devices that simulates additional RAM. • It enables programs to run as if your computer had more RAM when all of the available RAM is being used. • It moves data and commands from RAM to the computer’s permanent storage device to allow space for new data and commands. • Virtual memory is slower than RAM. IT Fundamentals 26 • Read-only memory (ROM) also called nonvolatile memory or permanent memory is a chip on the motherboard prerecorded with instructions the computer uses to check its components to ensure they are working. • It also activates the software that provides the basic functionality of the computer when you turn on the computer. • The boot process is the set of events that occurs between the moment you turn on the computer and the moment you can begin to use the computer. IT Fundamentals 27 • Complementary metal oxide semiconductor (CMOS, pronounced “SEEmoss”) memory is a chip installed on the motherboard that is activated during the boot process and identifies where essential software is stored. • A small rechargeable battery powers CMOS so its contents are saved when the computer is turned off. IT Fundamentals 28 • Unlike ROM, which cannot be changed, CMOS changes every time you add or remove hardware; therefore, CMOS is often referred to as semipermanent memory. • CMOS stores the date and time because it retains its contents when the computer is turned off. IT Fundamentals 29 Storage Media • On a computer, all data and instructions are stored as files. • A computer file is a named collection of stored data. • An executable file contains the instructions that tell a computer how to perform a specific task. • A data file is created by a user; for instance, a report you write with a word processing program can be saved as a data file. IT Fundamentals 30 • Magnetic storage media store magnetized particles on a surface. data as • The most common magnetic storage device, a hard disk, also called a hard disk drive. • A hard disk contains several magnetic oxidecovered metal platters that are usually sealed in a case inside the computer. • You can also purchase external hard drives for extra or backup storage. IT Fundamentals 31 • Optical storage devices are polycarbonate discs coated with a reflective metal on which data is recorded using laser technology as a trail of tiny pits or dark spots on the surface of the disc. • Compact disk memory (CD)—you can read from them, but you cannot record additional data onto them. • On a CD-R, after the data is recorded, you cannot erase or modify it, but you can add new data to the disc, as long as the disc has not been finalized. • In contrast, you can re-record a CD-RW. IT Fundamentals 32 • Recordable DVD drives are also available. As with CDs, you can buy a DVD to which you can record only once, or a rewritable DVD to which you can record and then re-record data. • Recordable DVDs come in two formats, DVD-R and DVD+R, and likewise re-recordable DVDs come in two formats, DVD-RW and DVD+RW. • DVD drives on new computers are capable of reading from and writing to both -RW and +RW DVDs and CDs, as well as DVDs with two layers IT Fundamentals 33 • Flash memory (also called solid state storage) is similar to ROM except that it can be written to more than once. • Flash memory cards are small, portable cards encased in hard plastic to which data can be written and rewritten. • They are used in digital cameras, handheld computers, video game controllers, and other devices. IT Fundamentals 34 • A popular type of flash memory is a USB flash storage device, also called a USB drive or a flash drive. • USB drives for PCs are available in a wide range of sizes from 1 to 64 GB of data. • They are becoming more popular for use as a secondary or backup storage device for data typically stored on a hard disk drive. IT Fundamentals 35 Types of Input and Output devices INPUT AND OUTPUT IT Fundamentals 36 • The data or instructions you type into the computer are called input. • The result of the computer processing your input is referred to as output. • The computer takes care of the processing function; you need additional components, called peripheral devices, to accomplish the input and output functions. IT Fundamentals 37 Input Devices • You use an input device, such as a keyboard or a mouse, to input data and issue commands. • The computer can also receive input from a storage device. IT Fundamentals 38 • A scanner is a device that transfers the content on a piece of paper into memory • Microphones are another type of input device. • Input devices can be connected to the computer with cables or via a wireless connection. IT Fundamentals 39 Output Devices The most common devices for displaying output are monitors and printers Laser Printer Inkjet Printer IT Fundamentals 40 Monitor • The most common devices for displaying output are monitors and printers. Most flat panel monitors use LCD (liquid crystal display) technology, which creates the image you see on the screen by manipulating light within a layer of liquid crystal. • Flat-panel monitors labeled as LED (light emitting diode) monitors use LEDs to provide the backlight. LED backlighting is more energy efficient than ordinary backlighting. One problem with LCD is that when you view the monitor from an angle, it can be hard to see the images on it. LED backlighting helps solve this problem. IT Fundamentals 41 • Factors that influence the quality of a monitor’s output are screen size, resolution, and dot pitch. • Screen size is the diagonal measurement in inches from one corner of the screen to the other. • Resolution is the number of pixels the monitor can display. – Standard resolutions range from 640 × 480 to 1600 × 1200. • Dot pitch (dp) measures the distance between pixels, so a smaller dot pitch means a sharper image. A .28 or .26 dp is typical for today’s monitors. IT Fundamentals 42 Printer • A printer produces a paper copy of the text or graphics processed by the computer. • The most popular printers for business use are laser printers. They use the same technology as a photocopier; a temporary laser image is transferred onto paper with a powdery substance called toner. The speed of laser printers is measured in pages per minute (ppm).Color laser printers use several toner cartridges to apply color to the page. • A less expensive alternative to the laser printer is an inkjet printer. IT Fundamentals 43 Data Communication • The transmission of text, numeric, voice, or video data from one computer to another or to a peripheral device. • The four essential components of data communications are; – – – – Sender : The origin of the message Receiver : The destination of the message Channel : The medium for the data transfer Protocol: The rules that establish an orderly transfer of data between the sender and the receiver IT Fundamentals 44 Data Bus Refers to the path between the microprocessor, RAM, and peripherals that data pass through to other devices and parts of the computer. IT Fundamentals 45 Networks • A network connects one computer to other computers and peripheral devices, enabling you to share data and resources with others. • Basic characteristics – – – – – Network interface card (NIC) Network Operating System Client Server Other peripherals (Routers, Access points etc) IT Fundamentals 46 Typical Networking Environment IT Fundamentals 47 Telecommunication • It refers to a communicating over a comparatively long distance using a phone line or some other data conduit. • To make this connection, you must use a modulator-demodulator (modem). The modem converts the digital signals into analog, or continuous wave, signals (sound waves) that can traverse ordinary phone lines. IT Fundamentals 48 Internet • The Internet is the largest network in the world, connecting millions of people. It is referred to as network of networks. • With an internet connection, you can have access to the resources on the world wide web. • Hence, the internet is the physical connection and the web is a collection of sites that offer text & graphics and sound & animation resources through the hypertext transfer protocol resources. IT Fundamentals 49 Security Threats • Security refers to the steps a computer owner takes to prevent unauthorized use of or damage to the computer. • Threats are activities, people, & programs that is a source of danger to computer systems. • Examples of computer security threats are Malware, Viruses, Spyware, Adware etc. IT Fundamentals 50 • Malware: is a broad term that describes any program that is intended to cause harm or convey information to others without the owner’s permission. • Virus: A software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer. Worms and Trojan horses are specific types of viruses. • Antiviruses are software that checks a computer for viruses and prevents their spread. IT Fundamentals 51 Computer Software • Software is defined as written programs, procedures or rules and associated documentation that direct the computer to accomplish a task. • Software are divided into two major categories: System Software and Application Software. IT Fundamentals 52 Systems Software • System software helps the computer carry out its basic operating tasks. • System software manages the fundamental operations of the computer, such as loading programs and data into memory, executing programs, saving data to disks, displaying information on the monitor, and transmitting data through a port to a peripheral device. IT Fundamentals 53 Types of Systems Software • Operating Systems: operating system controls basic input and output, allocates system resources, manages storage space, maintains security, and detects equipment failure. E.g. Windows, Macintosh, Linux • Utilities: Are programs that augments the operating system by taking over some of its responsibility for allocating hardware resources. E.g. Antivirus, Backup, Firewall • Device Drivers: Handle the transmission protocol between a computer and its peripherals. E.g. Drivers IT Fundamentals 54 Application Software • Application software helps the user carry out a variety of tasks. • Application software has a variety of uses: 1. To make business activities more efficient. 2. To assist with graphics and multimedia projects. 3. To support home, personal, and educational tasks. 4. To facilitate communications. IT Fundamentals 55 Types of Application Software • Business: Is an application software that assists people in becoming more effective and efficient while performing their daily business activities. E.g. Microsoft Office • Graphics and Multimedia: E.g. CAD, Photoshop, Illustrator, Desktop Publishing • Home/ Personal / Educational: E.g. Encarta, Personal Microsoft Office, Personal Email clients, CBTs etc. • Communication: E.g. Web browsers, IM apps, blogs, etc. IT Fundamentals 56 COMPUTING IN THE CLOUD IT Fundamentals 57 Cloud computing • Cloud computing means that data, applications, and even resources are stored on servers accessed over the Internet rather than on users’ computers, and you access only what you need when you need it. • Some companies provide space and computing power to developers for a fee. • Individuals might subscribe to a backup service such as Carbonite or Mozy so that their data is automatically backed up on a computer at the physical location of those companies. IT Fundamentals 58 • Google Docs and Microsoft Web Apps provide both free and paid versions of various applications that you access by logging in to their Web sites. • In addition to using services over the Internet, many people store files on servers accessed over the Internet. • For example, SkyDrive is space on Windows Live servers where you can store up to 25 GB of files in public or private folders or in folders that you make available to only people you specify. IT Fundamentals 59 Reference Ann Shaffer, Patrick Carey, June Jamrich Parsons and Dan Oja (2010). New Perspectives on Microsoft Office 2010, First Course, Course Technology. IT Fundamentals 60