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GRADE 9 WORKBOOK Teaching the skills of tomorrow...today Name : ____________________ School : ____________________ Grade : ____________________ DEAR ALL STUDENT GRADE 9C, E FOR -FINAL 1ST SEMESTER EXAM- ONLY READ FROM THE HIGHLIGHTED PARTS BEST OF LUCK.... Hello friends, I’m Techno Wizard, your new IT friend. Learning computers is easy and I’m going to make it more easy combined with fun. Teaching computer skills to you is going to be a whole new power packed experience for the future. So, what are you waiting for? Turn in and unveil a vast world of technology at your hands. P.S. : I’m in there. See you then... TECHNOKIDS INC. - GRADE 9 1 Copyright c Technokids Inc. All rights Reserved Revised Edition Publisher Technokids M.E. TechnoKids Workbook is published by TechnoKids M.E. Technokids is a trademark of TechnoKids Inc. Copyright © All Rights Reserved. This book may not be duplicated in whole or in part without the expressed written consent of the publisher, except in the form of brief excerpts or quotations for the purposes of review. The information contained herein is for personal of the reader and may not be incorporated in any other books, published documents, or any kind of software without written consent of the publisher. Making copies of this book or any portion for any purpose other than personal use is a violation of international copyright laws. Limits of Liability and Disclaimer of Warranty The publisher of this book has used their best efforts in preparing the lessons and activities contained. These efforts include the proper planning, research, development and testing of the theories incorporated in the programs to determine the effectiveness. The publisher makes no warranty of any kind, expressed or implied, with regards theories and concepts applied to the program or the documentation contained in this book. The publisher shall not be liable in the event of incidental or consequential damages in connection with, or arising out of, the furnishing, performance or use of the programs, associated instructions and/or claims of productivity gains. Trademarks Trademarked names appear throughout this book. Rather than list the names and entities that own trademarks or insert a trademark symbol with each mention of the trademarked name, the publisher states that it is using the names for editorial purposes only and to the benefit of the trademark owner, with no intention of infringing upon the trademark. Knowledge Hub, PO Box No. 234711, Office 103, Century Plaza, Jumeirah Beach Road, Dubai, United Arab Emirates +971-4-3856650 +971-4-3856652 [email protected] www.knowledge-hub.com TechnoKids Head Office 2097 Bates Common Burlington, ON L7R 0A5, Canada 1.905.631.9112 1.905.631.9113 [email protected] Preface In the present age of technology, computers have become an integral part or our daily life. In fact, computer literacy has brought to the forefront a pressing need to initiate the learner to all three aspects of computing – theory, application, and programming. TechnoKids Workbook is a series of six (6) books appropriately graded for students. The series has made use of the interactive approach, so that our young readers are drawn into actively participating in the learning process. There is also an attempt to enhance students’ creativity and inculcate behavior skills such as sharing and co-operating in the laboratory through this series. A sojourn through the series will expose the learner to a range of well structured material and instructions, at every stage of all operations. Each chapter has a plenty of illustrations, and subject matter along with screen shots of Windows and Office program environments for explanation and easy understanding. Our mission is to combine education and technology to provide children with the core computing skills that will best prepare them for the future. ISBN:978-1-940231-25-9 Table of Contents Chapter 1: Introduction to Computer 1 Chapter 2: F undamentals of Internet and WWW TECHNOKIDS INC. - GRADE 9 24 Chapter 3: Software 40 Chapter 4: Hardware 53 Chapter 5: Input and Output 69 Chapter 6: Storage 83 4 Chapter 1 INTRODUCTION TO THE COMPUTER In this chapter, the students become aware of the history of Computer, start to distinguish between the generations, the hardware and software, categories of computers. HISTORY OF COMPUTERS Today, it is hard to imagine life without computers. They have made a strong impact on our society. Computers find application in many areas; business, health care, telecommunication, engineering, entertainment, and education to name a few. In order to fully understand computers, and their impact on our day-to-day lives, it is important to understand their evolution. The development of computers from early calculating devices to the present can be broadly classified into the following categories: • Mechanical calculating devices • Electromechanical calculating devices, and • Electronic computers Early Counting Tools Our ancestor counted with the only counting tools they knew, their fingers and toes. These were considered the first counting tools. Soon man realized that other objects needed to be used to keep up with larger numbers. Some of the other counting tools that have been used throughout time have been stones, knots on ropes (quipu), and notches on sticks, notches on bones, tally sticks, to name just a few. People used these counting tools to count their possessions and also to keep tract of the passing of time. Bones Quipu TECHNOKIDS INC. - GRADE 9 1 CHAPTER - 1 Abacus Approximately 4,000 years ago, the Chinese invented the Abacus. It was the first machine used for counting and calculating. It is made of a wooden frame, metal rods, and wooden beads. Today, the abacus is still used widely in China and other Asian countries to count and calculate, just as we use calculators. John Napier In the early 17th century, John Napier, a Scottish mathematician, invented another calculating tool. It used marked strips of wood or bone, side by side, to multiply and divide. This tool became known as “Napier’s Bones.” Blaise Pascal 1640 Pascal’s adding machine (Pascaline) – one of the first semiautomatic mechanical devices, the pascaline, was developed by Blaise Pascal. This brass rectangular box had eight movable dials to add sums up to eight digits long. Joseph-Marie Jacquard 1801 Joseph-Marie Jacquard devised a mechanical loom, called Jacquard’s loom, which made weaving complex patterns a lot easier. The device used instructions stored on a punched card to control the movement of threads. TECHNOKIDS INC. - GRADE 9 2 CHAPTER - 1 Jacquard’s loom Joseph Jacquard Herman Hollerith Herman Hollerith 1890 Herman Hollerith (Feb 29, 1860 – Nov 17, 1929) was an American statistician and inventor who developed a mechanical tabulator based on punched cards to rapidly tabulate statistics from millions of pieces of data. He was the founder of the Tabulating Machine Company that later merged to become IBM in 1924. Hollerith is widely regarded as the father of modern machine data processing. With his invention of the punched card evaluating machine the beginning of the era of automatic data processing systems was marked. His draft of this concept dominated the computing landscape for nearly a century. Herman Hollerith Charles Babbage 1901 English mathematician Charles Babbage, often called the ‘father of the computer’, proposed a machine called the difference engine to compile mathematical tables. Charles Babbage proposed another machine, the analytical engine, which had the basic elements of a modern general-purpose computer. TECHNOKIDS INC. - GRADE 9 3 CHAPTER - 1 Augusta Ada Byron, Countess of Lovelace Much of what we know about Babbage and his machine comes from the papers of Augusta Ada Byron, countess of Lovelace and daughter of the poet Lord Byron. lady Lovelace was a genius in math. curious about Babbage’s work, she translated an article about the analytical engine from French to English. she added some important notes of her own about how the machine should work. She outlines the fundamentals of computer programming, including data analysis, looping and memory addressing. Her work has long outlived her, however. She is now called “the first programmer,” and a programming language used chiefly by the U.S. government was named Ada in her honor. Mark 1 1943 Harvard Mark I – American computer engineer Howard H. Aiken devised the IBM Automatic Sequence Controlled Calculator or Harvard Mark I. It was used for creating ballistic charts for the US Navy. Though slower in comparison to modern computers (taking about 3 to 4 seconds per calculation), it could perform basic arithmetic as well as more complex calculations. One of the primary programmers for the Mark I was a woman,Grace Hopper. Hopper found the first computer “bug”: a dead moth that had gotten into the Mark II and whose wings were blocking the reading of the holes in the paper tape. The word “bug” had been used to describe a defect since at least 1889 but Hopper is credited with coining the word “debugging” to describe the work to eliminate program faults. The offending moth was taped into the log book alongside the official report, which stated: “First actual case of a bug being found.” TECHNOKIDS INC. - GRADE 9 4 CHAPTER - 1 FIRST GENERATION The first generation computers were huge, slow, expensive, and often undependable. Vacuum tubes were invented the same time the light bulb was invented by Thomas Edison and worked very similar to light bulbs. Its purpose was to act like an amplifier and a switch. Without any moving parts, vacuum tubes could take very weak signals and make the signal stronger (amplify it). Vacuum tubes could also stop and start the flow of electricity instantly (switch). ENIAC and EDVAC 1946 ENIAC is the first general purpose electronic digital computer, as well as EDVAC, BINAC and UNIVAC I invented by John William Mauchly was an American physicist who, along with J. Presper Eckert, designed, the first commercial computer made in the United States. UNIVAC 1 1950 UNIVAC stands for Universal Automatic Computer 1 was one of the 1st commercially available computers. One of the UNIVAC’s impressive early achievements was correctly predicting Dwight D. Eisenhower’s victory in the 1952 US Presidential Election. IBM Model 701 1953 The IBM 701, known as the Defense Calculator while in development, was announced to the public on April 29, 1952, and was IBM’s first commercial scientific computer. Its business computer siblings were the IBM 702 and IBM 650. It was based on the IAS machine. IBM 701 process frame IBM 701 operator’s Console SECOND GENERATION The second generation (1954-1959) of computers used transistors for the internal operations. They used magnetic core for the memory. These machines also used assembly language. TECHNOKIDS INC. - GRADE 9 5 CHAPTER - 1 Transistors A transistor is a semiconductor device used to amplify and switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor’s terminals changes the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits. THIRD GENERATION Third generation (1959-1971) computers were based on “integrated circuits” (or microchips). Integrated circuit has several interconnected transistors, Eg: IBM’s 360 series computers. Jack Kilby and Robert Noyce 1958 Jack St. Clair Kilby (November 8, 1923 – June 20, 2005) was an American electrical engineer who took part (along with Robert Noyce) in the realization of the first integrated circuit while working at Texas Instruments (TI) in 1958. He was awarded the Nobel Prize in physics on December 10, 2000. To congratulate him, US President Bill Clinton wrote, “You can take pride in the knowledge that your work will help to improve lives for generations to come.” He is also the inventor of the handheld calculator and the thermal printer, for which he has patents. Robert Norton Noyce (December 12, 1927 – June 3, 1990), nicknamed “the Mayor of Silicon Valley”, co-founded Fairchild Semiconductor in 1957 and Intel Corporation in 1968. He is also credited (along with Jack Kelby) with the realization of the first integrated circuit or microchip which fueled the personal computer revolution and gave Silicon Valley its name. AT & T Bell labs 1960 Bell Laboratories (also known as Bell Labs and formerly known as AT&T Bell Laboratories and Bell Telephone Laboratories) is the research and development subsidiary of Alcatel-Lucent. The historic laboratory originated in the late 19th century as the Volta Laboratory and Bureau created by Alexander Graham Bell. TECHNOKIDS INC. - GRADE 9 6 CHAPTER - 1 Bell Labs was also at one time a division of the American Telephone & Telegraph Company (AT&T Corporation), half-owned through its Western Electric manufacturing subsidiary. Researchers working at Bell Labs are credited with the development of radio astronomy, the transistor, the laser, Bell’s 1893 Volta Bureau building in the charge-coupled device (CCD), information theory, the Washington, D.C UNIX operating system, the C programming language, S programming language and the C++ programming language. Seven Nobel Prizes have been awarded for work completed at Bell Laboratories. IBM 360 1964 The IBM System/360 Model 30 was a popular IBM mainframe announced in 1964 across the world as the then least powerful of the System/360s – the first line of computers in the world to allow machine language programs to be written that could be used across a broad range of compatible sizes. The Model 30 had a maximum main storage of 64K bytes; its CPU used an 8-bit microarchitecture with only a few hardware registers; everything that the programmer saw was emulated by the micro program. Floppy drive 1971 Alan Field Shugart (September 27, 1930 – December 12, 2006) was an American engineer, entrepreneur and business executive whose career defined the modern computer disk drive industry. He began his career at IBM in San Jose, California. He worked on the IBM 305 RAMAC, and rose through a series of increasingly important positions to become the Direct Access Storage Product Manager, responsible for its disk storage products. Those were IBM’s most profitable businesses at that time. Among the groups reporting to Shugart was the team that invented the floppy disk. FOURTH GENERATION Fourth Generation (1971 – present) computers are based on “microprocessors”. This generation can be characterized by both the jump to monolithic integrated circuits (millions TECHNOKIDS INC. - GRADE 9 7 CHAPTER - 1 of transistors put onto one integrated circuit chip) and the invention of the microprocessor (a single chip that could do all the processing of a full-scale computer). By putting millions of transistors onto one single chip more calculation and faster speeds could be reached by computers. Because electricity travels about a foot in a billionth of a second, the smaller the distance the greater the speed of computers. Atari and Intel processor 1972 A microprocessor incorporates the functions of a computer’s central processing unit (CPU) on a single integrated circuit (IC), or at most a few integrated circuits. All modern CPUs are microprocessors making the micro- prefix redundant. The microprocessor is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and provides results as output. It is an example of sequential digital logic, as it has internal memory. Microprocessors operate on numbers and symbols represented in the binary numeral system. This generational and chronological list of Intel processors attempts to present all of Intel’s processors from the pioneering 4-bit 4004 (1971) to the present high-end offerings, which include the 64-bit Itanium 2 (2002), Intel Core 2, and Xeon 5100 and 7100 series processors (2006). Concise technical data are given for each product. Apple 1976 Steven Paul “Steve” Jobs (February 24, 1955 – October 5, 2011) was an American entrepreneur, marketer, and inventor, who were the co-founder, chairman, and CEO of Apple Inc. Jobs received a number of honors and public recognition for his influence in the technology and music industries. He has been referred to as “legendary,” a “futurist” and a “visionary,” and has been described as the “Father of the Digital Revolution,” a “master of innovation,” “the master evangelist of the digital age” and a “design perfectionist.” Stephen Gary “Steve” Wozniak (born August 11, 1950), known as “Woz”, is an American inventor, electronics engineer, and computer programmer who co-founded Apple Computer (now Apple Inc.) with Steve Jobs and Ronald Wayne. Wozniak single-handedly designed both the Apple I and Apple II computers in the late 1970s. These computers contributed significantly to the microcomputer revolution. TECHNOKIDS INC. - GRADE 9 8 CHAPTER - 1 Apple II, Commodore PET, TRS-80 1977 The Apple II (styled as apple) is an 8-bit home computer, one of the first highly successful mass-produced microcomputer products, designed primarily by Steve Wozniak, manufactured by Apple Computer (now Apple Inc.) and introduced in 1977. It is the first model in a series of computers which were produced until Apple II e production ceased in November 1993. The Commodore PET (Personal Electronic Transactor) is a home/personal computer produced in 1977 by Commodore International. A top-seller in the Canadian and United States educational markets, it was Commodore’s first full-featured computer, and formed the basis for their entire 8-bit product line. TRS-80 (“Tandy/Radio Shack, Z-80 microprocessor”) was a brand associated with several desktop microcomputer lines sold by Tandy Corporation through their Radio Shack stores. Motorola Processor 1979 The Motorola MC10800 was a 4-bit bit-sliced processor designed by Motorola and introduced in 1979. It was implemented in ECL logic and was part of the M10800 family. The 6800 (“sixty-eight hundred”) was an 8-bit microprocessor designed and first manufactured by Motorola in 1974. The MC6800 microprocessor was part of the M6800 Microcomputer System that also included serial and parallel interface ICs, RAM, ROM and other support chips. IBM PC 8086 Processor 1981 The IBM Personal Computer, commonly known as the IBM PC, is the original version and progenitor of the IBM PC compatible hardware platform. It is IBM model number 5150, and was introduced on August 12, 1981. It was created by a team of engineers and designers under the direction of Don Estridge of the IBM Entry Systems Division in Boca Raton, Florida. The generic term “personal computer” was in use before 1981, applied as early as 1972 to the Xerox PARC’s Alto. However, because of the success of the IBM Personal Computer, the term PC came to mean more specifically a desktop microcomputer compatible with IBM’s PC TECHNOKIDS INC. - GRADE 9 9 CHAPTER - 1 products. Within a short time of the introduction, third-party suppliers of peripheral devices, expansion cards, and software proliferated; the influence of the IBM PC on the personal computer market was substantial in standardizing a platform for personal computers. In 1981 International Business Machines (IBM), one of the world’s largest companies dominated the computer industry. Apple Lisa first GUI 1983 The Lisa is a personal computer designed by Apple Computer, Inc. during the early 1980s. It was the first personal computer to offer a graphical user interface in an inexpensive machine aimed at individual business users. Development of the Lisa began in 1978. In 1982, after Steve Jobs was forced out of the Lisa project, he joined the Macintosh project. The Macintosh is not a direct descendant of Lisa, although there are obvious similarities between the systems. The final revision, the Lisa 2/10, was modified and sold as the Macintosh XL. Macintosh 1984 The Macintosh, or Mac, is a line of personal computers (PCs) designed, developed, and marketed by Apple Inc. It was initially targeted mainly at the home, education, and creative professional markets. Since the introduction of the Macintosh, the computer has seen significant evolution, now making it one of the most powerful general purpose computers on the market. It now targets the business, science, and law markets as well. Steve Jobs introduced the Macintosh 128K on January 24, 1984. This was the first mass-market personal computer featuring a graphical user interface and mouse. The 128 was followed by numerous updated models also based on the Motorola 68000 family processors, producing a family of products in the Macintosh lineup. Although the aggressively priced IBM Personal Computer soon overtook Apple in sales, Macintosh systems found success in education and desktop publishing and kept Apple as the second-largest PC manufacturer until 1994 when it was overtaken by Compaq. TECHNOKIDS INC. - GRADE 9 10 CHAPTER - 1 CD ROM 1985 CD-ROM is a pre-pressed optical compact disc which contains data. The name is an acronym which stands for “Compact Disc Read-Only Memory”. Computers can read CD-ROMs, but cannot write on the CD-ROM’s which are not writable or erasable. Pentium Processor 1993 The Intel Pentium microprocessor was introduced on March 22, 1993. Its microarchitecture, dubbed P5, was Intel’s fifthgeneration and first superscalar IA-32 microarchitecture. As a direct extension of the 80486 architecture, it included dual integer pipelines, a faster floating-point unit, wider data bus, separate code and data caches and features for further reduced address calculation latency. In 1996, the Pentium with MMX Technology (often simply referred to as Pentium MMX) was introduced with the same basic microarchitecture complemented with an MMX instruction set, larger caches, and some other enhancements. AMD Athlon and Pentium III processor 1999 Athlon is the brand name applied to a series of x86compatible microprocessors designed and manufactured by Advanced Micro Devices (AMD). The original Athlon (now called Athlon Classic) was the first seventh-generation x86 processor and, in a first, retained the initial performance lead it had over Intel’s competing processors for a significant period of time. The original Athlon also had the distinction of being the first desktop processor to reach speeds of one gigahertz (GHz). AMD has continued using the Athlon name with the Athlon 64, eighth-generation processor featuring x 86-64 (later renamed AMD64) architecture, and the Athlon II. The Athlon made its debut on June 23, 1999. Athlon comes from the Greek (athlos) meaning ″contest. The Pentium III (marketed as Intel Pentium III Processor, informally PIII, also stylized as Pentium !!! ) brand refers to Intel’s 32-bit x86 desktop and mobile microprocessors based on the sixth-generation P6 microarchitecture introduced on February 26, 1999. The brand’s initial processors were very similar to the earlier Pentium II-branded microprocessors. TECHNOKIDS INC. - GRADE 9 11 CHAPTER - 1 Pentium 4 Processor 2000 Pentium 4 is a line of single-core desktop and laptop central processing units (CPUs) introduced by Intel on November 20, 2000 and shipped through August 8, 2008. They had a 7th -generation x86 microarchitecture, called NetBurst, which was the company’s first all-new design since the introduction of the P6 microarchitecture of the Pentium Pro CPUs in 1995. NetBurst differed from P6 (Pentium III, II, etc.) by featuring a very deep instruction pipeline to achieve very high clock speeds. Intel claimed that NetBurst would allow clock speeds of up to 10 GHz; however, severe problems with heat dissipation (especially with the Prescott Pentium 4) limited CPU clock speeds to a much lower 3.8 GHz. In 2004, the initial 32-bit x86 instruction set of the Pentium 4 microprocessors was extended by the 64-bit x86-64 set. Multi core Processor Opteron Series Processor AMD 2005 Opteron is AMD’s x86 server and workstation processor line, and was the first processor which supported the AMD64 instruction set architecture (known generically as x86-64). It was released on April 22, 2003 with the SledgeHammer core (K8) and was intended to compete in the server and workstation markets, particularly in the same segment as the Intel Xeon processor. Processors based on the AMD K10 microarchitecture (codenamed Barcelona) were announced on September 10, 2007 featuring a new quad-core configuration. The most-recently released Opteron CPUs are the Pile driver-based Opteron 4300 and 6300 series processors, codenamed “Seoul” and “Abu Dhabi” respectively. Intel Core Duo 2006 Core 2 is a brand encompassing a range of Intel’s consumer 64-bit x86-64 single-, dual-, and quad-core microprocessors based on the Core microarchitecture. The single- and dual-core models are singledie, whereas the quad-core models comprise two dies, each containing two cores, packaged in a multi-chip module. The introduction of Core 2 relegated the Pentium brand to the mid-range market, and reunified laptop and desktop CPU lines, which previously had been divided into the Pentium 4, Pentium D, and Pentium M brands. TECHNOKIDS INC. - GRADE 9 12 CHAPTER - 1 FIFTH GENERATION 5th Generation (Present and Beyond) Still Being Developed, Natural Language- This language is designed to give people a more human connection with computers. Uses multi-media has also defined this generation. There is a great deal of “bundled software” with this generation. Artificial intelligence (AI) is the intelligence exhibited by machines or software. It is also an academic field of study. Major AI researchers and textbooks define the field as “the study and design of intelligent agents”, where an intelligent agent is a system that perceives its environment and takes actions that maximize its chances of success. John McCarthy, who coined the term in 1955, defines it as “the science and engineering of making intelligent machines”. Artificial intelligence (AI) is the computer application that has fueled the continual effort to create faster and more powerful machines. The goal of AI is to develop computers that can perform functions normally reserved for humans: thinking, talking, seeing, feeling, walking, and learning from their mistakes. Artificial Intelligence Technology Trends The current trend in AI development is moving toward limited, focused applications. Rather than attempting to perform the broad range of tasks humans can perform, modern AI systems focus on simulating specialized human function. Instead of replacing humans, the goal of AI has shifted to augmenting human capabilities rather than supplanting them. The three primary areas of artificial intelligence application are cognitive science, natural interfaces, and robotics. COMPUTERS AND COMPUTER SYSTEM A computer system comprises hardware, software and networks. Hardware: The physical components of a computer system are called hardware. A computer system basically consists of the following physical components. System Unit, Input Devices, Output Devices, I/O devices TECHNOKIDS INC. - GRADE 9 13 CHAPTER - 1 COMPONENTS OF COMPUTER SYSTEM Hardware Overview Computer hardware is the collection of physical elements that constitutes a computer system. Computer hardware refers to the physical parts or components of a computer such as the monitor, mouse, keyboard, computer data storage, hard drive disk (HDD), system unit (graphic cards, sound cards, memory, motherboard and chips), etc. all of which are physical objects that can be touched. In contrast, software is instructions that can be stored and run by hardware. a. system unit c. output devices b. input devices e. Communication devices d. Storage devices Software Overview Software is a set of computer programs ( a set of instructions that perform a particular task), procedures, and associated documentation related to the effective operation of a computer system. Software directs the computer to perform input operations, process the data, and output the results. It is classified in to the following categories. • System software • Application software CATEGORIES OF COMPUTER PERSONAL COMPUTER The microcomputer is the most common type of computer. Microchips are used in these computers. Desktop Computer Microcomputers are usually called desktop personal computers or desktop PCs. Desktop computers consists of : a base units, or tower unit, that contains a CPU and backing storage devices, input devices normally a mouse and key board, output devices typically a screen, projector, printer and speakers. TECHNOKIDS INC. - GRADE 9 14 CHAPTER - 1 Advantages Easily upgraded to include new software or hardware They are relatively robust and can be used almost continually for very long periods of time It is possible to ‘mix and match’ specifications and components, in effect creating a custom made machine Monitors come in a range of sizes and qualities and can be chosen specifically to suit the user’s preferences It is easy to replace an individual part if damaged or burn out They can run a vast range of software, often simultaneously. They can be physically screwed down thus making them fairly secure from theft. Disadvantages Desktop PCs are not easily portable. They are large and heavy. They require a large amount of permanent office space. They need a fan to prevent overheating. Thus they can be fairly noisy. They can only be run on main electricity and need to be situated near to a power point. New advances in technology means that PCs get out of date very quickly Portable Computer Portable computers are smaller than desktop PCs and can be easily carried around. The most common type of portable computer is the laptop which, as the name suggests, will fit comfortably on a user’s lap. Other types of portable computer include palmtops and PDAs (Personal Digital Assistants); these are much smaller than laptops and will fit in a shirt or jacket pocket. Both palmtops and PDAs can be linked to user’s laptop allowing data to be synchronized so that it is the same on both devices. Advantages They are portable and very easy to carry around. They can be used almost anywhere e.g. airports They are light to carry. Older laptops were fairly heavy, but advances in technology and much improved batteries have allowed them to become very lightweight. They are compact and can be easily stored in a standard briefcase. They can replace almost all of the functions of a Desktop PC They make use of the same peripheral equipment as the desktop e.g. printers They are quiet to run as unlike a Desktop PC, there is often only a small (or no) cooling fan creating a noise. TECHNOKIDS INC. - GRADE 9 Disadvantages They are more expensive to purchase than a similar Desktop PC They cannot be expanded in the same way as a Desktop PC e.g. new graphics cards, more memory. They are attractive to thieves and can be easily stolen. They are fairly expensive to repair. They are easily damaged if dropped. Can run on battery power for only a relatively short time, usually between 1-6 hours. The screen may be small if needed for detailed work e.g., CAD/CAM design, The keyboards can be cramped if used for long periods of time. 15 1 CHAPTER - 3 Handheld Computer A handheld PC, or H/PC for short, is a computer built around a form factor which is smaller than any standard laptop computer. It is sometimes referred to as a palmtop. The first hand-held device compatible with desktop IBM personal computers of the time was the Atari Portfolio of 1989. Other early models were the Pocket PC of 1989 and the Hewlett Packard HP 95LX of 1991. Other DOS - compatible hand - held computers also existed. A typical PDA has a touchscreen for entering data, a memory card slot for data storage, and Bluetooth and/or Wi-Fi. Advantages Disadvantages Small, can easily be fitted into a pocket or The screen small handbag Lightweight to carry – typically 200g Keyboards tend to be small and cramped Simple to use Where a stylus is used to handwrite, a new language called Graffiti needs to be learnt Long battery life compared with laptop (up to They cannot be easily upgraded 30 hours) Power up immediately when they are turned They cannot be used for such a wide range of on, no need to go through boot up sequence tasks as the laptop or Desktop Many have cut down versions of common They are easy to steal. office software. They can be connected to a desktop PC or They can be damaged if dropped. Laptop and the files can be transferred over. Many (but not all) Palmtops and PDAs are They have a relatively small amount of memory much lower in cost than PCs or Laptops and cannot store large amounts of data. WORKSTATION A workstation is a special computer designed for technical or scientific applications. Intended primarily to be used by one person at a time, they are commonly connected to a local area network and run multi-user operating systems. The term workstation has also been used loosely to refer to everything from a mainframe computer terminal to a PC connected to a network, but the most common form refers to the group of hardware offered by several current and defunct companies such as Sun Microsystems, Silicon Graphics, Apollo Computer, DEC, HP and IBM which opened the door for the 3D graphics animation revolution of the late 1990s. TECHNOKIDS INC. - GRADE 9 16 CHAPTER - 1 Midrange Server Midrange computers, or midrange systems, are a class of computer systems which fall in between mainframe computers and microcomputers. IBM favored the term ‘midrange computer’ for their comparable more business-oriented System/3, System/34, System/32, System/36, System/38, and AS/400 ranges. Since the 1990s, when the client–server model of computing became predominant, computers of the comparable class are instead universally known as servers to recognize that they usually “serve” end users at their “client” computers. Mainframe Computer Mainframe computers (colloquially referred to as “big iron”) are computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning and transaction processing. The term originally referred to the large cabinets called “main frames” that housed the central processing unit and main memory of early computers. Later, the term was used to distinguish highend commercial machines from less powerful units. Most large-scale computer system architectures were established in the 1960s, but continue to evolve. Advantages Disadvantages They are used by large companies such as – They are very expensive Gas and Electricity suppliers – for billing Banks- for managing accounts They are operated by specialist, trained Ordinary users normally use a terminal to personnel and kept in air-conditioned rooms access the system. away from the office or factory floor. Supercomputer A supercomputer is a computer at the frontline of contemporary processing capacity – particularly speed of calculation which can happen at speeds of nanoseconds. Supercomputers were introduced in the 1960s, made initially and, for decades, primarily by Seymour Cray at Control Data Corporation (CDC), Cray Research and subsequent companies TECHNOKIDS INC. - GRADE 9 17 CHAPTER - 1 bearing his name or monogram. While the supercomputers of the 1970s used only a few processors, in the 1990s machines with thousands of processors began to appear and, by the end of the 20th century, massively parallel supercomputers with tens of thousands of “offthe-shelf” processors were the norm. As of November 2013, China’s Tianhe-2 supercomputer is the fastest in the world at 33.86 petaFLOPS, or 33.86 quadrillion floating point operations per second. Supercomputer main uses Weather forecasting Space exploration Advanced scientific research Military establishment – weapons research Pharmaceutical \ Drug testing Supercomputers cost over a hundred million pounds to build and need specifically designed rooms and environments to ensure that they operate efficiently There can be many miles of cables which connect the computer to the various peripherals. In ordered to hide this, false floors and ceilings are often needed Smoke detectors are essential to help detect any fires immediately The atmosphere must be kept free of dust particles. Special filters have to be installed to ensure that the air is kept clean. Supercomputers generate so much heat that an air conditioning system is required. TECHNOKIDS INC. - GRADE 9 18 CHAPTER - 1 EXERCISES Answer the following questions 1) Who is called the ‘Father of the computers’? ___________________________________________________________________ 2) Who invented the tabulating machine? ___________________________________________________________________ 3) Name the first general purpose electronic digital computer? ___________________________________________________________________ 4) Computers of which generation were based on transistors? ___________________________________________________________________ 5) IBM’s PC and Apple’s Macintosh are examples of which generational computers? ___________________________________________________________________ ___________________________________________________________________ 6) Where is AT & T Bell labs located? ___________________________________________________________________ 7) What is the use of Floppy Drive and who was invented? ___________________________________________________________________ ___________________________________________________________________ 8) What is Desktop Computer? ___________________________________________________________________ ___________________________________________________________________ 9) What is workstation? ___________________________________________________________________ ___________________________________________________________________ TECHNOKIDS INC. - GRADE 9 19 CHAPTER - 1 10) Write any two advantages of main-frame computer? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ 11) Write any two dis-advantages of super computer? ___________________________________________________________________ ___________________________________________________________________ 12) Write briefly about portable computer? ___________________________________________________________________ ___________________________________________________________________ 13) Write short notes on handheld computer? ___________________________________________________________________ ___________________________________________________________________ Long-answer questions 1) Write short notes on the following A. ABACUS a. ABACUS B. JACQUARD’S LOOM C. HARVARD MARK1 ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ b. JACQUARD’S LOOM ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ TECHNOKIDS INC. - GRADE 9 20 CHAPTER - 1 c. HARVARD MARK1 ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ 1) Write short notes on Personal Computers? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Multiple choice questions 1) 2) 3) What did first generation computers use for circuitry? a. transistors b. vacuum tubes c. integrated circuits d. microprocessors What did second generation computers use for circuitry? a. transistors b. vacuum tubes c. integrated circuits d. microprocessor What was the main technology used in third generation computers? a. vacuum tubes b. integrated circuits c. microprocessors TECHNOKIDS INC. - GRADE 9 21 CHAPTER - 1 d. 4) 5) 6) 7) 8) artificial intelligence What was the main technology used in fourth generation computers? a. vacuum tubes b. integrated circuits c. microprocessors d. artificial intelligence Fifth generation computers are based on which of the following? a. vacuum tubes b. integrated circuits c. microprocessors d. artificial intelligence The Pascaline was developed by a. Blaise Pascal b. Gottfried Wilhelm von Leibnitz c. Charles Babbage d. Herman Hollerith ………….. The Analytical Engine was designed by a. Blaise Pascal b. Gottfried Wilhelm von Leibnitz c. Charles Babbage d. Herman Hollerith Harvard Mark I was a. a manual calculating device b. a semi-automatic calculating device c. an electromechanical calculating device d. an electronic computer TECHNOKIDS INC. - GRADE 9 22 CHAPTER - 1 9) A computer developed by John Mauchly and J. Presper Eckert. a. ABC b. Macintosh c. ENIAC d. Z3 10) What are the examples of electromechanical calculating devices? a. The Tabulating machine and Harvard Mark I b. ENIAC, EDVAC c. EDSAC, ENIAC d. EDVAC, UNIVAC I TECHNOKIDS INC. - GRADE 9 23 CHAPTER - 1 Chapter 2 UNDAMENTALS OF INTERNET F AND WWW In this chapter, the students understand the ABCs of Internet and WWW. INTERNET The internet is a global system of interconnected computer networks that use the standard internet protocol suite (TCP/IP) to link several billion devices worldwide. It is an international network of networks that consists of millions of private, public, academic, business, and government packet switched networks, linked by a broad array of electronic, wireless, and optical networking technologies. Advantages Information is more up-to-date; Information can be accessed at any time of day or night; Information is available as sound and video as well as text; Information can be obtained direct from experts using chat and e-mail Information is presented in electronic format allowing it to be reused. Using the internet is more interesting than working with books in a library. Disadvantages Some sources of information are unreliable, biased or incorrect Access to information can be slow unless an expensive high-speed connection is available Information cannot be accessed if computers break down or the internet connection is broken. People need to know how to use a computer in order to access the information. It can take longer to find the right information compared with being told which books to look in. Internet Activities Individuals, organizations, businesses and governments use the Internet to accomplish a number of activities. It is sub divide into categories: • Communication • Entertainment TECHNOKIDS INC. - GRADE 9 24 CHAPTER - 2 • Electronic Commerce • Research • Distance Learning COMMUNICATION One of the most important ways information technology is used today is to distribute exchange and share information. Electronic communication systems are what we use to do this. Here are some ways to share information: Electronic Mail E-mail or electronic mail, is sued to send messages from one computer to another. Email can be sent between computers on a local area network or between computers on the internet. Chat Room The term chat room, or chat room, is primarily used to describe any form of synchronous conferencing, occasionally even asynchronous conferencing. Synchronous conferencing is the formal term used in computing, in particular in computer-mediated communication, collaboration and learning, to describe technologies informally known as online chat. It is sometimes extended to include audio/video conferencing or instant messaging systems that provide a text-based multi-user chat function. In contrast, Asynchronous conferencing is the formal term to describe technologies where there is a delay in interaction between contributors. Instant Messaging Instant messaging (IM) is a type of online chat which offers real-time text transmission over the Internet. Blog A blog is a website where someone (usually a normal person - not a professional writer) writes about a topic. It can be personal (someone writing about their own life, or their personal views), based on an interest (e.g. football), or some businesses also use blogs to write about new products, etc. It allows someone to be a writer and publisher on the Web with very little effort or cost. TECHNOKIDS INC. - GRADE 9 25 CHAPTER - 2 The word ‘blog’ is an abbreviation of ‘web log’. Social Networks A social network website is a site that allows user to connect with other users who are friends / relatives, or who share similar interests. Connected users can then share information / pictures / files with each other, send messages, chat, etc. Message Board or Internet forum An Internet forum, or message board, is an online discussion site where people can hold conversations in the form of posted messages. They differ from chat rooms in that messages are often longer than one line of text, and are at least temporarily archived. Also, depending on the access level of a user or the forum set-up, a posted message might need to be approved by a moderator before it becomes visible. Forums have a specific set of jargon associated with them; e.g. a single conversation is called a “thread”, or topic. Streaming Video Sites Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a provider Live streaming, which refers to content delivered live over the Internet, requires a camera for the media, an encoder to digitize the content, a media publisher, and a content delivery network to distribute and deliver the content. Telecommuting Telecommuting is a work arrangement in which employees do not commute to a central place of work. A person who telecommutes is known as a telecommuter. File Transfer Protocol The File Transfer Protocol (FTP) is a standard network protocol used to transfer computer files from one host to another host over a TCP-based network, such as the Internet. TECHNOKIDS INC. - GRADE 9 26 CHAPTER - 2 ENTERTAINMENT Using computer for entertainment purposes is a common activity among Internet users of all ages. Computers are adept of outdoing almost all entertainment devices. Online Games An online game is a video game played over some form of computer network. This network is usually the internet or equivalent technology, but games have always used whatever technology was current: modems before the Internet, and hard wired terminals before modems. Music and Video Music and Video from various Internet sources can be downloaded and played on computers. Moving Picture Expert Group Layer III (MP3) is the most widely used music file format. While for videos there are many formats such as MPEG, MP4 and WMV formats. ELECTRONIC COMMERCE Electronic commerce, commonly known as E-commerce or e-Commerce, is trading in products or services conducted via computer networks such as the Internet. It is commonly divided into two categories; business-to-consumer (B2C) and business-to-business (B2B). RESEARCH Search Engines are software programs available at Web sites that stores searchable snapshots of the information found on millions of other Web sites. DISTANCE LEARNING Distance education, distance learning, d-learning, or D-Learning is a mode of delivering education and instruction, often on an individual basis, to students who are not physically present in a traditional setting such as a classroom. It provides access to learning when the source of information and the learners are separated by time and distance, or both. Distance education courses that require a physical on-site presence for any reason (including taking examinations) TECHNOKIDS INC. - GRADE 9 27 CHAPTER - 2 have been referred to as hybrid or blended courses of study. Massive open online courses (MOOCs), aimed at large-scale interactive participation and open access via the web or other network technologies, are a recent development in distance education. Education was a high priority in the Progressive Era, as all high schools and colleges expanded greatly in the world. LINKING TO THE INTERNET Millions of people throughout the world are able to connect to the Internet. But to connect you to the internet, you need computer, a modem, telephone line and last is an Internet Service Provider (ISP). An internet service provider is a commercial organization which provides a connection to the Internet for other businesses or individuals. DIFFERENT INTERNET CONNECTION Dial-up connection The simplest way to connect to the Internet is to use a dialup connection. This type of connection requires a computer with a modem and access to a telephone line. Because dial-up access uses normal telephone lines the quality of the connection is not always good and data rates are limited. Typical Dial-up connection speeds range from 2400 bps to 56 Kbps. SYSTEM MODEM Digital Signal MODEM Analog SYSTEM Digital Signal Digital Subscriber Line Digital subscriber line (DSL, originally digital subscriber loop) is a family of technologies that provide Internet access by transmitting digital data over the wires of a local telephone network. This is possible because DSL uses higher frequency bands for data. DSL connection speeds range from 128 Kbps to 9 Mbps. TECHNOKIDS INC. - GRADE 9 28 CHAPTER - 2 Cable Modem A cable modem is a type of Network Bridge and modem that provides a broadband Internet connection that is designed to operate over cable TV lines. Cable modems are having high bandwidth for extremely fast access. Cable providers typically implement a cap to limit capacity and accommodate more customers. Cable speeds range from 512 Kbps to 20 Mbps. Wireless Wireless networking is used to meet many needs. Perhaps the most common use is to connect laptop users who travel from location to location. Instead of using telephone or cable networks for your Internet connection, you use radio frequency bands. Wireless Internet provides an always-on connection which can be accessed from anywhere — as long as you geographically within a network coverage area. Satellite Internet over Satellite allows a user to access the Internet via a satellite that orbits the earth. A satellite is placed at a static point above the earth’s surface, in a fixed position. Because of the enormous distances signals must travel from the earth up to the satellite and back again, It is slightly slower than high-speed terrestrial connections over copper or fiber optic cables. Typical Internet over satellite connection speeds (standard IP services) average around 492 up to 512 Kbps. ROUTING THE INTERNET Web navigation refers to the process of navigating a network of information resources in the World Wide Web, which is organized as a hypertext or hypermedia. Surfing is an activity to know how to navigate using browser to access the web. WEB BROWSER A web browser (commonly referred to as a browser) is a software application for retrieving, presenting and traversing information resources on the World Wide Web. An information TECHNOKIDS INC. - GRADE 9 29 CHAPTER - 2 CHAPTER - 2 resource is identified by a Uniform Resource Identifier (URI/URL) and may be a web page, image, video or other piece of content. The 4 most popular web browsers are Internet Explorer, Google Chrome, Mozilla Firefox and Safari. Capabilities of Browser •Automatic identification and connection to any local port providing a connection to the Internet • HTML code viewing (the language of web pages) • Java applet support(special programs written for the web) •Easy-to-use interfaces that allow for control commands such as a favorites list, a stop access button, and a go-back button. INTERNET PROTOCOL Web browsers locate material on the Internet using IP – Internet Protocol addresses. An IP address works like an Internet Phone number. It is a four-group series of numbers separated by periods, such as 207.171.181.16, representing a server on the Internet. Since remembering IP numbers would be difficult, every computer also has corresponding Web address called a Uniform (or Universal) Resource Location (URL). A URL constitutes a pathname describing where the information can be found on the internet. WEB PAGE A Web page is the term for a single document viewable on the WWW. A web site comprises all of the web pages composing the site. The first web page displayed when a Website is accessed is usually the site’s home page. Like the table of contents in a book, the home page is an overview of the information and features contained within the site. HTML HTML or Hyper Text Markup Language is the standard markup language used to create web pages. TECHNOKIDS INC. - GRADE 9 30 CHAPTER - 2 HTML is written in the form of HTML elements consisting of tags enclosed in angle brackets (like <html>). HTML tags most commonly come in pairs like <h1> and </h1>, although some tags represent empty elements and so are unpaired. This called markup language. A Hypertext document presents information enhanced with link to other document. This presentation method allows user to read only basic information or clicks the link to access additional information on another web page. Technically called a hyperlink, a web link is any element on the screen that is coded in HTML used on web pages as a means of navigating around. XML XML stands for eXtensible Markup Language • XML was designed to transport and store data. • HTML was designed to display data. • XML is a markup language much like HTML • XML was designed to carry data, not to display data • XML tags are not predefined. A user must define a user own tags • XML is designed to be self-descriptive • XML is a W3C Recommendation XML Does Not DO Anything Maybe it is a little hard to understand, but XML does not DO anything. XML was created to structure, store, and transport information. XML is Not a Replacement for HTML • XML is a complement to HTML. •It is important to understand that XML is not a replacement for HTML. In most web applications, XML is used to transport data, while HTML is used to format and display the data. • XML is a software- and hardware-independent tool for carrying information The Difference between XML and HTML • XML is not a replacement for HTML. • XML and HTML were designed with different goals: TECHNOKIDS INC. - GRADE 9 31 CHAPTER - 2 • XML was designed to transport and store data, with focus on what data is • HTML was designed to display data, with focus on how data looks • HTML is about displaying information, while XML is about carrying information. AUDIO, VIDEO AND ANIMATION ELEMENT Most computer users are accustomed to the basic elements of a web page that attract and hold the interest of those viewing the page, such as text, photos, and links. Various mini programs make these additional possible, including Java applets, and plug-ins such as Shockwave, Apple QuickTime, Adobe Acrobat Reader, and Flash Player. Java Applets Java applet is a small application which is written in Java and delivered to users in the form of bytecode. (Java applets are small Java programs Web browsers run. An applet is the term for a miniature program). It can appear in a frame of the web page, a new application window. Cookies A cookie, also known as an HTTP cookie, web cookie, or browser cookie, is a small piece of data sent from a website and stored in a user’s web browser while the user is browsing that website. Plug ins A plug-in (or plugin, extension, or add-on / addon) is a software component that adds a specific feature to an existing software application. When an application supports plug-ins, it enables customization. The common examples are the plug-ins used in web browsers to add new features such as search-engines, virus scanners, or the ability to utilize a new file type such as a new video format. ADVERTISEMENT Advertisement is a notice or announcement in a public medium promoting a product, service, or event or publicizing a job vacancy. Advertising on the World Wide Web is a recent phenomenon. Prices of Web-based advertising space are dependent on the “relevance” of the surrounding web content and the traffic that the website receives. TECHNOKIDS INC. - GRADE 9 32 CHAPTER - 2 Banner A web banner or banner ad is a form of advertising on the World Wide Web delivered by an ad server. It is intended to attract traffic to a website by linking to the website of the advertiser. The advertisement known as a “click through.” In many cases, banners are delivered by a central ad server. Pop-up Window Pop-up ads or pop-ups are often forms of online advertising on the World Wide Web intended to attract web traffic or capture email addresses. Pop-ups are generally new web browser windows to display advertisements. Blind Links Some links misrepresent their true function. A frequently encountered example is a link with wording such as “Next Page”, that actually directs viewers to an advertising web page. This deception is called a blind link, and reputable web page designers consider it bad form.. A blind link is a link on a web page that does not take a user to the web address that it is supposed to. Hi-Jacker A Browser Hijacker is a program that changes the home page or search settings of an installed web browser without user permission. VALUING THE INTERNET COMMUNITY Internet users around the world form a community and, like any social organization, the community exhibits the entire range of behavior, from considerate and creative to insulting and damaging. The word netiquette is a combination of ’net’ (from internet) and ’etiquette’. It means respecting other users’ views and displaying common courtesy when posting your views to online discussion groups TECHNOKIDS INC. - GRADE 9 33 2 CHAPTER - 4 Netiquette is a collection of rules and guidelines that define good Net behavior. The basic rules •Refrain from personal abuse. You may express robust disagreement with what someone says, but don’t call them names or threaten them with personal violence. •Don’t spam. That is, don’t repeatedly post the same advertisement for products or services. Most sites have strict and specific rules about who is allowed to post ads and what kind of ads they are. •Write clearly and succinctly. On a site that has many non-native English speakers, avoid using slang they may not understand. •Remember that your posts are public. They can be read by your partner, your children, your parents, or your employer. •Stay on-topic, especially when you’re new. Don’t post about football in a hair-care forum or about hair care in a gardening forum! •Don’t expect other people to do your homework for you. If you’re looking for technical help, for example, don’t ask questions you could easily answer yourself by reading the manual or online help provided with the product. When you do ask for help, include details of what attempts you’ve made to solve the problem. It will save time and also show people that you are making an effort to help yourself. •Do not post copyrighted material to which you do not own the rights. Sites vary in how strict they are about this, but as well as facing the possibility of legal action by the rights holder, you may also get the site sued. •The site’s owner, perhaps assisted by one or more moderators, has the final say in enforcing the rules. • Adhere to the same standards of behavior online that you follow in a real life • know where you are in cyberspace • respect other people’s time and bandwidth • make yourself look good online • share expert knowledge • help keep flame wars under control TECHNOKIDS INC. - GRADE 9 34 CHAPTER - 2 • respect other people’s privacy • don’t abuse your power E-mail Suggestion Some specific suggestions for composing and sending e-mail may help in using netiquette. The ease with which e-mail can be composed and send makes it very easy to make mistakes that might be regretted later. There are several very important points to remember when writing and sending e-mail messages: • Once sent, they cannot be retrieved • A permanent copy of an e-,ail message probably remains • E-mail is easily forwarded or copied. For these reasons it is always a good idea to avoid sending any e-mail messages that have been written in anger or haste. It is better to save the e-mail, and then look at it again later when emotions have cooled. If the writer still feels that the e-mail should be sent, she still has that option. However, in most cases she will realize that sending the e-mail would not be a good idea, and may be something she should later regret. Once the send button is clicked, it is too late to do anything. Spam: Unwanted Communication E-Mail Spam – An example of bad Net behavior is the significant and growing number of e-mail messages that are considered junk e-mail, or spam. Spam is the name given to unsolicited e-mails (ones sent without being asked for).Spam e-mails usually contain adverts for products... Lawmakers are contemplating further measures to control spam, since the e-mail servers that must receive all of this unwanted mail require billions of dollars’ worth of extra capacity just to process and screen and spam floods, which grow larger each year. MODERATED ENVIRONMENT Moderated environments are the answer for many people who want to avoid the seedy side of the Net. Many chat rooms, message boards, and mailing lists have a moderator, an individual with the power to filter messages and ban people who break the rules. Rules violations can be anything from hurling insults to simply straying off-topic. TECHNOKIDS INC. - GRADE 9 35 CHAPTER - 2