New Gateway to Computer Science 8

GATEWAY TO COMPUTER SCIENCE NEW BOOK 8 With Video Tutorials Our Computer Series 1. New Gateway to Computer Science-1 2. New Gateway to Computer Science-2 3. New Gateway to Computer Science-3 4. New Gateway to Computer Science-4 5. New Gateway to Computer Science-5 6. New Gateway to Computer Science-6 7. New Gateway to Computer Science-7 8. New Gateway to Computer Science-8 9. New Gateway to Computer Science-9 10. New Gateway to Computer Science-10 Our Computer Series Price Rs. 429/- GATEWAY TO COMPUTER SCIENCE NEW BOOK With 8 Video Tutorials Shubharambha Publication Pvt.Ltd. Kathmandu Nepal New Gateway to Computer Science Book - 8

Authors Dinesh Adhikari Dilendra Prasad Bhatt Laxman Adhikari Shekhar Poudel Shubharambha Publication Pvt. Ltd. Kathmandu, Nepal NEW GATEWAY TO COMPUTER SCIENCE 8 Approved by Government of Nepal, Ministry of Education, Curriculum Development Centre, Sanothimi, Bhaktapur as an Additional Learning Material.

Authors : Dinesh Adhikari, Dilendra Prasad Bhatt, Laxman Adhikari, Shekhar Poudel Layout Design : Ram Malakar Video Content : Dinesh Adhikari Language Editor : Krishna Prasad Regmi Copyright © : Dinesh Adhikari Edition :First 2076 B.S. Second 2077 B.S. ISBN : 9789937579315 © : Publisher No part of this book may be reproduced or transmitted by means (electronic, photocopying, recording or otherwise) without prior written permission from the publisher. Any breach of this condition will entail legal action and prosecution. Shubharambha Publication Pvt.Ltd. Kathmandu, Nepal URL: www.shubharambhapublication.com E-mail: [email protected] www.facebook.com/shubharambhapublication Published by: New Gateway to Computer Science Book-8 Printed in Nepal

It has become a fundamental right of children to get computer education. It is very essential to get basic to advance knowledge about computer education to compete the future. Nepal government has prescribed the syllabus and course outline for the computer education from primary to higher secondary level. But students are not able to get quality education due to the lack of systematic course book and the computer system in the school. So we have developed the complete series of computer science. Along with the evolution of human beings new thoughts, area of knowledge and technology also developed together. Among the eruptions, ICT (Information and Communication Technology) is one which has unquestionably become important part of human beings. A person is not better than a caged pigeon if s/he is far from computer technology in this century. New Gateway to Computer Science is a complete package which obviously supports a lot to the students as this is one of the most useful Text Book, so far available in the market. This book is completely prepared considering the level of the students. This text has the various salient features like it focuses on child psychology, pictorial descriptions, video tutorials, quiz section, practical sections, etc. How to get video tutorials? 1. Install QR code reader apps on your mobile device (smart phone) from play store. 2. After installation, open the apps from your device. 3. When you open this apps, a camera will appear. 4. Move your camera over the QR code picture (Scan here for video tutorials) that is provided in your text book. 5. Now QR code reader automatically scans it and displays the link of related video. 6. Touch on the link and open it in YouTube for video tutorials. Ensure that you have internet connection before scanning the code from the text book. It is impossible to acknowledge all who have directly or indirectly encourage me to prepare this book on this single page. My special thanks goes to the students and teachers of different schools for their regular interactions during the preparation of this book. Comments and constructive suggestions are highly welcomed from the readers and professionals to update this text book. Dinesh Adhikari [email protected] Preface

Content Unit 1: Fundamental Knowledge and Skill of Computer 5-161 1. Fundamental Concept of Computer.....................................................6-11 2. History of Computer Development..................................................12-22 3. Generation of Computer....................................................................23-30 4. Types of Computer............................................................................31-40 5. Introduction to Computer Hardware & Software..............................41-51 6. Operating System..............................................................................52-78 7. Word Processing Program-2010......................................................79-108 8. Spreadsheet Software-2010...........................................................109-131 9. Presentation Software-2010...........................................................132-161 Unit 2: ICT, Computer Ethics and Cyber Law 162-211 10.Web Page Designing with HTML.................................................163-175 11. Information and Communication Technology...............................176-181 12.Computer Ethics and Cyber Law..................................................182-189 13.Computer Virus.............................................................................190-197 14.Introduction to Computer Networking..........................................198-211 Unit 3: Computer Number System 212-221 15.Computer Number System............................................................213-221 Unit 4: Computer Graphics and Multimedia 222-252 16. Introduction to Computer Graphics..............................................223-245 17.Multimedia and Application..........................................................246-252 Unit 5: Concept of Computer Programming 253-289 18.Program Designing Tools and Techniques......................................254-261 19.Fundamental Knowledge of Computer Programming..................262-266 20. Computer Programming in QBASIC ...........................................267-289 Practical Time....................................................................................284 Specification Grid...............................................................................290 Model Question.................................................................................291

Fundamental Knowledge and Skill of Computer Unit 1 Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Fundamental Concept of Computer History of Computer Development Generation of Computer Types of Computer Introduction to Computer Hardware & Software Operating System Word Processing Program-2010 Spread Sheet Software-2010 Presentation Software-2010 Inside the Unit

6 New Gateway to Computer Science Book-8 Introduction Today is the world of computers as every field is dependent on it. A computer is a powerful tool developed by the human. Computers have reshaped our lives at home, office, school and other various places. The computer is a basic part of human life. The life of human is almost impossible without it. The computers have not only enhanced the efficiency of the user but also have changed the lifestyle of human. It is a machine that performs calculations and processes information with amazing speed and accuracy. They can help us in solving many complex tasks and improving the quality of our lives. It can help in producing actual result, help in teaching and assist in removing various human errors. Working principle of computer A computer is a machine that receives and processes data according to the instructions given to it, and after the data has been processed, the results of the processing are usually sent to an output device. The computer system works on the principle of input-process and output. Fundamental Concept of Computer 1 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • describe the working principle of computer. • tell the advantages and disadvantages of computer. • explain the basic computer terminologies.

7 New Gateway to Computer Science Book-8 Input Computer gets data and instruction from the input devices like keyboard, mouse, scanner, microphone, light pen, etc. Input is the act of entering data and instructions to the computer for processing. Processing When a computer gets the input with the help of input devices then it starts to process the data for the user. The CPU is responsible to do these activities in the computer system. Keyboard Mouse Monitor Backing Storage Printer Device Input Devices Computer (CPU) Output Device Disk drive Output After the data are processed they go to the output devices such as the monitor. The main task of an output unit is to display the result. The output is always meaningful. The output devices can be a screen (monitor), printer, plotter, speakers,etc. A computer is a powerful tool developed by the human. The life of human is almost impossible without computer. A computer is a machine that performs calculations and processes information with amazing speed and accuracy. A computer is a machine that receives and processes data according to the instructions given to it. Computer gets data and instruction from the input devices like keyboard, mouse, scanner, microphone, light pen, etc. Input is the act of entering data and instructions to the computer for processing. The CPU is responsible to do the processing activities in the computer system. The main task of output unit is to display the result. The output devices can be a monitor, printer, plotter, speakers, etc. Quick Learn

8 New Gateway to Computer Science Book-8 Advantages and disadvantages of computer Advantages Computers are 100% accurate machine. Computer is fast and accurate device. Computer is a versatile machine. It has high storage capacity. Computers can be used in various fields for different purposes. Disadvantages It is expensive system so it is not easily accessible for poor people. Physical damage may occur at any time. It is totally human dependent so it cannot work without human instructions. It is creating unemployment problem. It is a non-intelligence device. Basic computer terminologies Data Data are the collection of raw facts which do not carry out any specific meaning. Name of students, number of students, marks secured by the students in their exam, etc. are the examples of data. Information Information is the collection of data presented in a systematic way which has the special meaning. The information is always meaningful. Program Programs are the collection of many instructions together in sequence and in a logical way to solve the problems. A computer requires programs to function and execute the program’s instructions in a central processing unit. Hardware Computer hardware is the collection of physical parts of the computer system. This includes the computer case, monitor, keyboard, and mouse. It also includes all the parts inside the computer case, such as the hard disk drive, motherboard, video card, and many others. Computer hardware is what you can physically touch. • TYPEWRITER is the longest word that you can write using the letters only on one row of the keyboard. • Doug Engelbart invented the first computer mouse in around 1964 which was made of wood. • The first 1GB hard disk drive was announced in 1980 which weighed about 550 pounds, and had a price of $40,000. Exploring Knowledge!

9 New Gateway to Computer Science Book-8 Software Computer software is a set of programs and related documentation that tells the computer what to do and how to perform a task. Computer software needs hardware to function properly. Command Commands are the instructions or order given to the computer to do some specific task. The commands are dependent on programming languages and operating system being used. Memory Computer memory is any physical device capable of storing information temporarily or permanently. Volatile and non-volatile are the types of memory. Non-volatile memory is a permanent type of computer memory whereas volatile memory is a temporary type of computer memory. RAM (Random Access Memory) It is the internal memory of the CPU for storing data, program and program result. It is read/write memory which stores data until the machine is working. As soon as the machine is switched off, data are erased so it is called volatile memory. Computers are 100% accurate machine. Data is the collection of raw facts which does not carry out any specific meaning. Information is the collection of data presented in a systematic way which has the special meaning. Programs are the collection of many instructions together in sequence and in a logical way to solve the problems. Hardware is the collection of physical parts of the computer system. Software is a set of instructions and related documentation that tells the computer what to do or how to perform a task. Computer software needs hardware to function properly. Commands are the instructions or order given to the computer to do some specific task. Volatile and non-volatile are the types of memory. RAM is a volatile memory. Quick Learn • The house where Bill Gates lives, was designed using a Macintosh computer. • The first hard disk drive was madein 1979, and could hold only 5MB of data. • The original name of windows was Interface Manager. Exploring Knowledge!

10 New Gateway to Computer Science Book-8 1. Fill in the blanks with suitable words. a. A computer is a machine that performs calculations and processes information with amazing ………….. and ………………. b. A computer is a machine that receives and processes data according to the……… given to it. c. The ………is responsible to do the processing activities in the computer system. d. ……………is the collection of data presented in a systematic way which has the special meaning. e. …………….. is the collection of physical parts of a computer system. f. Computer software needs ………………… to function properly. 2. State whether the following statements are true or false. a. A computer is a powerful tool developed by the nature. b. Computer gets data and instruction from the input devices like keyboard, mouse, scanner, microphone, light pen, etc. c. Output is the act of entering data and instructions to the computer for processing. d. Computers are 100% accurate machine. e. Data are the collection of raw facts which do not carry out any specific meaning. f. Programs are the collection of many instructions together in a sequence and in logical way to solve some problems. g. Hardware is a set of instructions and related documentation that tells a computer what to do or how to perform a task. 3. Match the following. Hardware Set of computer programs Software Physical parts of the computer Memory Instructions Output Storage devices Command Final result EXERCISE

11 New Gateway to Computer Science Book-8 4. Write down the full forms of the followings. CPU , IPO , RAM 5. Write very short answer the following questions. a. Define the term ‘Computer’. b. What is ‘Input’? c. What are data? d. What is the working principle of the computer? e. Why does a computer need programs? f. What is Random Access Memory? g. What are the types of internal memory? 6. Write short answer to the following questions. a. Write any two advantages and disadvantages of the computer. b. Write about the computer hardware and software. c. What is the computer memory? What is the role of the memory in a computer? d. What is hardware and software? Write with examples. 7. Write long answer to the following questions. a. Explain the working principle of the computer with clear diagram. b. Explain, why the computer is powerful working tool? Project Work & Activity a. Conduct a presentation program about the advantages and disadvantages of the computer. b. Prepare a definition chart of any five computer terminologies and submit it to your teacher.

12 New Gateway to Computer Science Book-8 Introduction The history of computer was started from the Stone Age. Many inventors worked a lot for the development of different calculating devices. During that time, so many devices were developed for calculating and to do mathematical calculations. We are living in the age of computer. Almost our daily activities are not possible without these calculating devices. It is used increasingly in each and every field of our life. The history of calculations was started with the abacus but, first such machine having principle of today’s computing machine was developed by Charles Babbage in 19th century. According to the technology and concept used on devices, there were three types of calculating devices such as manual calculating device, electro mechanical and electronic computers. Mechanical Calculating Devices Abacus Abacus was used by the Chinese people to perform calculations. It is being used throughout the world. It was made up of wooden frame in which rods were fitted across with round beads sliding on the rod. It is divided into two parts called ‘Heaven’ and ‘Earth’. Heaven is the upper part and Earth is the lower part. The lower parts and the upper parts are divided by the mid bar so that any number can be represented by placing the beads at proper place. History of Computer Development 2 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • explain various mechanical calculating devices. • define various electro-mechanical calculating devices. • identify the electronic calculating devices. • tell the history of computer in Nepal.

13 New Gateway to Computer Science Book-8 Napier’s Bone John Napier, a Scottish mathematician and politician developed a machine called Napier’s Bone in 1617 AD. In 1614 AD he developed the concept of logarithm. He worked on this idea for almost two decades before the concept of logarithms came into effect. Napier also made improvements to the idea of the decimal fraction by starting the use of decimal points; a practice that very soon became common throughout Britain. John Napier invented the ‘Napier Bones’ which were devices that could be used as calculators. They were called ‘bones’ because they were made out of ivory. Ivory is a hard, white material from the tusks and teeth of animals. Slide Rule It was the invention of William Oughtred which was introduced in 1620 AD. The slide rule was based on logarithm. It was a mechanical analog device that was used for making numerical computations and reading such as multiplication, division, powers, roots, functions, etc. The slide rule is actually made up of three bars that are fixed together. The sliding centre bar is sandwiched by the outer bars which are fixed with respect to each other. The metal “window” is inserted over the slide rule to act as a place holder. A cursor is fixed in the centre of the “window” to allow for accurate readings. Pascaline Pascaline also called as Pascalene is a calculating machine developed by Blaise Pascal in 1642 AD when he was of 19 years. This was the first practical calculating device. It is a numerical wheel calculator which had 8 movable dials. It worked on the principle of rotating wheels. This machine could only do addition, subtraction and multiplication by the repeated addition and division by repeated subtraction. The numbers of calculating capacity of Pascaline was 9,99,99,999. It utilizes a mechanical gear system to add and subtract with as many as eight columns of digits Konrad Zuse invented the first computer Z1 in 1936 AD and Z2 in 1939 as the first electro-mechanical computer in the world. Blaise pascal was born on June 19, 1623 and died on August 19, 1662 in Paris, France. The first computer mouse was made up of the wood. Exploring Knowledge!

14 New Gateway to Computer Science Book-8 Stepped Reckoner A German mathematician Gottfried Wilhelm Von Leibniz invented a calculating machine known as Leibniz’s Wheel (Stepped Reckoner) in 1673 AD. It was used in many calculating machine till 1970 AD. The Stepped Reckoner expanded on Pascal’s ideas and did multiplication by repeated addition and shifting. The Stepped Reckoner was based on a gear mechanism that Leibniz invented and that is now called a Leibniz wheel. The machine can: add or subtract an 8-digit number to / from a 16-digit number. multiply to 8-digit numbers to get a 16-digit result. divide a 16-digit number by an 8-digit divisor. Abacus was the first manual calculating device developed by the Chinese people before 3000 BC. Abacus was made up of the wooden frame. The upper part of abacus is called heaven and the lower part is called earth. Slide rule was the invention of William Oughtred which was introduced in 1620 AD. Slide rule is also called the first analog device. William Oughtred also introduced the concept of logarithm. Blaise Pascal developed the device called Pascaline in 1642 AD. Pascaline was capable to do the calculations up to eight digits only. Gottfried Wilhelm von Leibniz invented Stepped Reckoner in 1673 AD. Stepped Reckoner was used in many calculating machine till 1970 AD. Quick Learn Jacquard’s Loom Joseph Marie Jacquard, a silk weaver, invented this machine in 1804 AD. This loom was the first to use punched card with punched holes. Jacquard’s technology was a real boon to mill owners, but put many loom operators out of work. The punched cards controlled the actions of the loom, allowing automatic production of intricate woven patterns. The punchedcard idea was adopted later by Charles Babbage about 1830 to control his Analytical Engine, and later by Herman Hollerith for tabulating the 1890 USA census.

15 New Gateway to Computer Science Book-8 Charles Babbage Charles Babbage was a popular mathematician, philosopher, inventor and mechanical engineer. He was the first person to develop the concept of modern digital computer which works on the principle of Input-process-output and storage so, he is known as the father of computer. Mathematical tables were important in Babbage’s era for use in navigation, science and engineering. They were calculated by hand and then compiled into tables. Errors were sometimes made either in the calculation or in the compiling of the tables. The inventions of Babbage are given below: Difference Engine It was the first invention of Babbage introduced in 1822 A.D. It was big in size. It was powered by the steam. Later on it was developed for commercial purpose also. It was an automatic mechanical calculator designed to tabulate polynomial functions. The name is derived from the method of divided differences, a way to include or tabulate functions by using a small set of polynomial coefficients. Analytical Engine It was the second invention of Babbage which was introduced in 1833 AD. The analytical engine was general purpose mechanical computer. This device contained the following components: The store (like a memory) The mill ( like a processing unit) The input section using punched card The output section using punched card. Lady Augusta Ada Lovelace Lady Augusta Ada Lovelace was a daughter of Lord Byron. She was born on December 1815 AD and died on November 1852 when she was of 36 years. She was the first to recognise that the machine had applications beyond pure calculation, and created the first algorithm proposed to be carried out by such a machine. As a result, she is often regarded as the first to recognise the full potential of a “computing machine” and the first computer programmer.

16 New Gateway to Computer Science Book-8 Charles Babbage was born on December 26, 1791, and died in October 18, 1871 in Marylebone, United Kingdom Grace Murray Hopper was a U.S. Naval officer, and an early computer programmer who was the developer of the first compiler for a computer pro gramming language. IBM is an American multinational technology company located in New York, USA. Exploring Knowledge! Hollerith Tabulating Machine The Hollerith tabulating machine was also known as the tabulating machine. It was an electrical counting machine invented by Herman Hollerith. In 1887 AD. He developed the system of Punched Card tabulating system in data processing. The card had been used earlier to control patterns in textile looms. He used this system to process the 1890 census. It was successful, and Hollerith found the Tabulating Machine Company, which later merged to become a company called IBM (International Business Machine). Hollerith tabulating machines were widely used throughout the first half of the 20th century, up to the 1940s and early 1950s. Joseph Marie Jacquard invented Jacquard’s Loom in 1804 AD. Charles Babbage is known as the father of the modern computer. Babbage was the first person to develop the concept of modern digital computer. The first invention of Babbage was difference engine which was developed in 1822 A.D. Analytical engine was the second invention of Babbage which was introduced in 1833 AD. Lady Augusta Ada Lovelace is known as the first computer programmer. Tabulating Machine Company was developed by Herman Hollerith. Quick Learn

17 New Gateway to Computer Science Book-8 Electro-Mechanical Calculating Devices Mark I The Harvard Mark I was the first electromechanical computer developed by Howard Aiken at Harvard University and built by IBM in 1937. The computer was 51 feet long, 8 feet high and weighed 5 tons. It provided vital calculations for the U.S. Navy during World War II and was the first of a series of computers designed by Aiken. At the time, it was publicized as the world’s first programmable computer. The Harvard Mark I was also known as the IBM Automatic Sequence Controlled Calculator (ASCC).The Harvard Mark I could perform four arithmetic operations like addition, subtraction, multiplication, division and had built-in programs for processing logarithms and trigonometric functions. The Mark I received instructions on paper tape and loaded data output on punch cards. . ABC ( Atanasoff Berry Computer) The Atanasoff-Berry Computer was the electro mechanical digital computer built in 1942 AD at Iowa State University by John Vincent Atanasoff and Clifford Berry. This computer is also called the first digital computer. It has electronic switching elements and could perform binary arithmetic. The main concepts of this computer are given below: It introduced the ideas of binary arithmetic, regenerative memory and logic circuit. It used 18000 valves and other 45 valves for internal logic and capacitors for storage of electrical charge. It used punch cards as secondary storage. Electronic Calculating Devices ENIAC (Electronic Numerical Integrator and Calculator) The first electronic computer was the Electrical Numerical Integrator and Calculator, known as ENIAC. It was designed by John Presper Eckert and John William Mauchly in 1946 AD. ENIAC was the first multipurpose electronic computer,

18 New Gateway to Computer Science Book-8 though very difficult to re-program. It was primarily used to computer aircraft courses, shell trajectories, and to break codes during the World War II. It was made up of 17,468 vacuum tubes, 70,000 registers, 10,000 capacitors, 1500 relay and 6,000 manual switches. It used decimal number system instead of binary number system. EDSAC (Electronic Delay Storage Automatic Calculator) EDSAC is an early British computer considered to be the first stored program electronic computer. It was created at the University of Cambridge in England. John von Neumann developed it in 1949 AD. It could add two numbers in 1500 microseconds and multiply them in 4000 microsecond. In this device 3000 vacuum tubes were used. It uses stored program concept for the first time and also use the binary numbers. UNIVAC (Universal Automatic Computer) The UNIVAC I was the first commercial computer produced in the United States. It was designed principally by John. Presper Eckert and John William Mauchly in 1951 AD. It was the first commercial general purpose digital computer. The use of this computer started from 1951 AD to 1970 AD. This device was 50 feet long and 25 feet wide. It was able to store 12,000 letters only. Magnetic tape were used as an input and storage. EDVAC (Electronic Discrete Variable Automatic Computer) John William Mauchly and John Presper Eckert developed this in 1952 AD but the construction was started from 1944 AD. It was the first computer based on stored program concept. This computer also worked on binary digits and used stored program concept. It used 6,000 vacuum tubes and 12,000 diodes which consumed 56 kilowatt power. It was popularly used upto 1961 AD. History of Computer in Nepal The history of ICT and computer in Nepal is not so long. The IBM 1401 belongs to the second generation computer which was introduced in Nepal for the first time in 2028 BS. This computer was brought on rent and after that another second generation mainframe computer ICL 2950/10 model was introduced in Nepal. To work with the technology, Yantrik Sarinikaran Kendra (Electronic Data Processing Centre) was

19 New Gateway to Computer Science Book-8 established which was later called as National Computer Centre (NCC). After 2039 B.S. microcomputer like; Apple , Vector, Sirus were introduced in Nepal. After the year of 2039 BS computers have been used in different government sectors like banking, agriculture, universities, etc. Now there are thousands of computer in states providing computer education, assembling, maintenance etc. throughout the country. These days the latest technologies and devices are available in our country. Google is founded by Sergey Brin and Larry Page on September 7, 1998. The World Wide Web Consortium is founded by Tim Berners-Lee. Apple introduces the Macintosh with mouse and window interface in 1984 AD. IBM created the first floppy disk in 1967 AD. Exploring Knowledge! Mark I was the first electromechanical calculating device developed by Howard Hathaway Aiken. Mark I is also known as Howard Mark I. It was built by IBM in 1937 AD. The Atanasoff-Berry Computer was the electromechanical digital computer built in 1942 AD at Iowa State University by John VincentAtanasoff and Clifford Berry. ABC is also called the first digital computer. ENIAC (Electronic Numerical Integrator and Calculator) was the first electronic computer designed by John Prosper Eckert and John William Mauchly in 1946 AD. ENIAC was the first multipurpose electronic computer. EDSAC (Electronic Delay Storage Automatic Calculator) was the first stored program electronic computer. EDSAC was created at the University of Cambridge in England. UNIVAC (Universal Automatic Computer) was the first commercial computer developed by John. Presper Eckert and John William Mauchly in 1951 AD. EDVAC (Electronic Discrete Variable Automatic Computer) was developed by John William Mauchly and John Presper Eckert in 1952 AD. EDVAC was the first computer based on stored program concept. Quick Learn

20 New Gateway to Computer Science Book-8 1. Choose the best answer from the given alternatives. a. Which of the following is the first manual calculating device? i. Babbage’s engine ii. Abacus iii. Napier’s Bone b. Who was the inventor of Napier’s Bone? i. William Jack ii. John Napier iii. Blasé Pascal c. Which of the following device was based on logarithm? i. Slide Rule ii. Abacus iii. Analytical Engine d. When was Stepped Reckoner invented? i. 1573 AD ii. 1773 AD iii. 1673 AD e. What was the first computer based on stored program concept? i. EDVAC ii. ENIAC iii. ABC f. Which was the first digital computer? i. ENIAC ii. IBM iii. ABC 2. . Fill in the blanks with suitable words. a. The upper part of abacus is called ….. and the lower part is called earth. b. …………..was the first analog device. c. ……………. is known as the father of the modern computer. d. Analytical engine was the second invention of …………… e. …………… is known as the first computer programmer. f. Tabulating Machine Company was developed by…………… g. …………… was the first electromechanical calculating device developed by Howard Hathaway Aiken. h. The ………was the electromechanical digital computer built in 1942 AD. i. ENIAC was the first ………………. computer designed by John Presper Eckert and John William Mauchly. j. …………. was the first stored program electronic digital computer. EXERCISE

21 New Gateway to Computer Science Book-8 3. State whether the following statements are true or false: a. Abacus was the first manual calculating device developed by the Chinese people. b. Slide rule was the invention of John Napier which was introduced in 1620 AD. c. Blaise Pascal developed a device called Pascaline in 1620 AD. d. Gottfried Wilhelm von Leibniz invented Stepped Reckoner in 1673 AD. e. Joseph Marie Jacquard invented Jacquard’s Loom in 1804 AD. f. Babbage was the first person to develop the concept of modern digital computer. g. The first invention of Babbage was analytical engine. h. Mark I is also called the Howard Mark I. It was built by IBM in 1937 AD. i. Slide rule is also called the first digital computer. j. ENIAC was the first multipurpose electronic computer. 4. Match the following: Difference engine First electronic computer Mark I UNIVAC ABC Charles Babbage ENIAC Howard H. Aiken First commercial computer First electromechanical computer 5. Write down the full forms of the followings: ABC , ENIAC , EDSAC , UNIVAC , EDVAC , NCC, IBM 6. Write very short answer to the following questions. a. What was the first manual calculating device? b. Who is known as the father of the modern computer technology? c. Who was the inventor of slide rule? d. What are the devices invented by Charles Babbage? e. Who is considered as the first computer programmer? f. Who was the inventor of Stepped Reckoner and when it was invented? g. Who was the founder of Tabulating Machine Company? h. How many vacuum tubes were used in the first electronic computer? i. Which generation of computer was introduced in Nepal for the first time?

22 New Gateway to Computer Science Book-8 7. Write short answer of the following questions: a. Describe in short about Abacus. b. Why is Babbage known as the father of modern computer science? c. What are the components of analytical engine? d. Write a few lines about ENIAC. e. What was the first electromechanical digital computer? When was it invented and who invented it? 8. Write long answer to the following questions: a. Explain about the inventions of Babbage. b. List out the mechanical, electromechanical and electronic computers and explain them in short. Project Work & Activity Name of Device Name of inventor(s) Date of invention Slide Rule Pascaline Napier’s Bone Stepped Reckoner Analytical Engine MARK I ABC ENIAC EDSAC UNIVAC EDVAC Divide your class in various groups and conduct a presentation competition on “The History of Development of the Computer”.

23 New Gateway to Computer Science Book-8 Introduction Computers are truly amazing machines. In previous chapter we discussed about the historical background of the computer. Computer Generation means the change in technology that the computers were being used. The term 'generation' was used to distinguish between varying hardware technologies. But nowadays, generation includes both hardware and software, which together make up an entire computer system. There are total five computer generations till date. Based on the period of development and the features combined, the computers are classified into different generations from first to fifth generation. Generation of computer Each generation has been discussed in detail along with their time period, memory component and features below: First Generation The period of first generation was 1946-1958 AD. First generation of computer started with using vacuum tubes as the basic components for memory and circuitry for CPU (Central Processing Unit). These tubes like electric bulbs produced a lot of heat. The vacuum tube was developed by Lee De Forest in 1908 AD. In this generation batch processing operating system were Generation of Computer 3 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • explain the generations of the computer. • tell the features of each generation of the computer. • identify the memory component of each generation of computer.

24 New Gateway to Computer Science Book-8 used. Punched cards, Paper tape, Magnetic tape were used as input and output devices. There were Machine code and electric wired board languages used. ENIAC (Electronic Numerical Integrator And Calculator), EDSAC (Electronic Delay Storage Automatic Calculator), EDVAC (Electronic Discrete Variable Automatic Computer), UNIVAC (Universal Automatic Computer), etc. were used during this generation. Feature of the first generation computers It uses vacuum tube technology as a memory component. It was unreliable. It could support only machine language. The cost was very expensive. It generated more heat and it was very large in size. It had very slow Input and Output device. It was not portable. The first generation computers used vacuum tubes for circuitry and magnetic drums for memory, and were often huge, taking up entire rooms. LEE DE FOREST was the inventor of Vacuum Tube. A vacuum tube is a device generally used to amplify a signal by controlling the movement of electrons in an evacuated space. Quick Learn Second Generation The period of second generation was 1959-1964. The memory component was transistor of this generation. John Bardeen and Walter Brattain were the inventors of transistors. These computers were cheaper, consumed less power, more compact in size, more reliable and faster than the first generation. In this generation, magnetic cores were used as primary memory and magnetic tape and magnetic disks as secondary storage devices. Assembly language and high level programming language like FORTRAN, COBOL were used during this generation. Batch processing and multiprogramming operating systems were used in this generation. IBM 1620, IBM 1401, IBM 7094, CDC 1604, CDC 3600, UNIVAC 1108 computers were used during second generation.

25 New Gateway to Computer Science Book-8 Feature of the second generation computers The memory component was transistors. It was more reliable than previous generation computers. The size was smaller because of the use of transistor. It generated less heat as compared to the first generation computers. It also consumed less electricity as compared to previous generation. It was faster than the first generation computers. The processing speed was measured in microsecond. The transistor was invented in 1947 by three scientists J. Bardeen, H.W. Brattain and W. Shockley. A transistor is a small device made up of semiconductor material like germanium and silicon. Second generation computers used the low level language i.e. machine level language and assembly language. Quick Learn Third Generation The period of third generation was 1964-1971 AD. The third generation of computer is marked by the use of Integrated Circuits (IC’s) in place of transistors. A single IC has many transistors, resistors and capacitors along with the associated circuitry. The IC was invented by Jack Kilby and Robert Noyce. This development made computers smaller in size, reliable and efficient. In this generation Remote processing, Time-sharing, Real-time, Multi-programming Operating System were used. High level languages like FORTRAN II, III, IV, COBOL, PASCAL PL/1, BASIC, ALGOL-68, etc. were used during this generation. IBM-360 series, Honeywell-6000 series, PDP(Personal Data Processor), IBM-370/168, TDC-316 computers were used during the third generation. The Common Business-Oriented Language (COBOL) programming language was invented. in 1960 AD. John Backus & IBM developed the FORTRAN Computer Programming Language in 1954 AD. Remote control was invented by Nikola Tesla in 1898 AD. Exploring Knowledge!

26 New Gateway to Computer Science Book-8 Feature of the third generation computers. The IC was used as memory component. It was more reliable. It was smaller in size and generated less heat. Magnetic disk was used as a storage unit. It was much faster. The processing speed was measured in Nano second. It consumed less electricity. It used monitor and keyboard as output and input unit. It was able to support high level programming languages. IC was invented by Robert Noyce and Jack Kilby. IC is a single component containing a number of transistors. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. Keyboards and monitors were developed during the period of third generation of computers. Quick Learn Fourth Generation The period of fourth generation is from 1972 to till date. The fourth generation of computers is marked by the use of microprocessor which is made with the help of Large Scale Integration (LSI) and Very Large Scale Integrated (VLSI) circuits. VLSI circuits having about 5000 transistors and other circuit elements and their associated circuits on a single chip made it possible to have microcomputers of fourth generation. Fourth Generation computers became more powerful, compact, reliable, and affordable. As a result, it gave rise to personal computer (PC) revolution. In this generation Time sharing, Real time, Networks, Distributed Operating System were used. All the Higher level languages like C and C++, DBASE, JAVA, Visual Basic, TCL/Tk, Visual basic, Visual C++, C# , Visual basic.NET etc. are the GUI based computer languages. The development of IC gave birth to a new field of microelectronics. ENIAC was the world first successful electronic computer which was developed by the two scientists namely J. P. Eckert and J. W. Mauchy. Exploring Knowledge!

27 New Gateway to Computer Science Book-8 PHP etc. are being used in this generation. Windows, UNIX, Linux, Mac OS are the popular operating system used by this generation. DEC 10, STAR 1000, PDP 11, CRAY-1 (Super Computer), CRAY-X-MP(Super Computer), IBM PC, Apple Macintosh computers are used in this generation. Feature of the fourth generations computers VLSI technology is used to produce a single microprocessor. It is cheaper and more portable than previous generations. It is very accurate and versatile. The working speed is upto picosecond and femtosecond. Very advanced type of input and output unit are used such as scanner, light pen, touch screen, etc. It brings great development in the field of networking. In 1981 AD. IBM introduced computer for the home user and in 1984 AD. Apple introduced the Macintosh microprocessor. Many high-level languages have been developed in the fourth generation such as COBOL, FORTRAN, BASIC, PASCAL and C language. The fourth generation computers became more powerful, compact, reliable and affordable. Quick Learn Fifth Generation The development of fifth generation is started from 1990 which is still incomplete. In the fifth generation, the VLSI (Very Large Scale Integration) technology became ULSI (Ultra Large Scale Integration) technology, resulting in the production of Bio Chips having more than ten million electronic components. This generation is based on parallel processing hardware and AI (Artificial Intelligence) software. AI is an emerging branch in computer science, which interprets means and method of making computers think like human beings. We can imagine that this computer will be able to use natural languages like English, Germany, French and even Nepali for the processing. Jack Kilby developed the concept of integrated circuit in 1958. The first IC was invented and used in1961. Ted Hoff produced the first micro processor in 1971 for Intel. The size of an IC is about ¼ square inch. Exploring Knowledge!

28 New Gateway to Computer Science Book-8 Feature of the fifth generation computers The concept of Artificial Intelligence (AI) will be used. It will be able to understand various natural languages. It will be able to think and decide. The operating speed will be faster than the fourth generation computers. It will create the advancement in Parallel Processing. Quick Learn S.N Name of generation Duration in AD. Memory Components Examples 1 First 1946-1958 Vacuum Tube ENIAC,EDSAC, EDVAC, UNIVAC etc. 2 Second 1959-1964 Transistors IBM 1620, IBM 1401, IBM 7094, CDC 1604 etc. 3 Third 1964-1971 Integrated Circuit IBM-360series, Honeywell-6000 series, PDP, IBM-370/168, TDC-316 etc. 4 Fourth 1972-till date Microprocessor DEC 10, STAR 1000, PDP 11, CRAY-1 etc. 5 Fifth Undergoing Bio-Chips Robot EXERCISE 1. Choose the best answer from the given alternatives. a. What was the memory component of the first generation computers? i. Slide Rule ii. Abacus iii. Vacuum Tube b. What was the programming language used by the first generations of computer i. High level language ii. Machine Language iii. Assembly Language

29 New Gateway to Computer Science Book-8 c. What was the name of programming language used by the second generations of computer? i. C++ ii. Flowchart iii. FORTRAN d. Which of the following is the third generations of computer? i. IBM 360 Series ii. ENIAC iii. IBM 1401 e. Robot is an example of: i. Second generation ii. Third generation iii. Fifth generation 2. Fill in the blanks with suitable words. a. …………….. was the inventor of Vacuum Tube. b. The transistor was invented in …………… c. ………. generation computers used the low level language i.e. machine level language and assembly language. d. IC is a single component containing a number of …………………. e. ……… were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. f. The memory component of the fourth generations of computer was ………… 3. State whether the following statements are true or false. a. The first generation computers used vacuum tubes for circuitry and magnetic drums for memory. b. A transistor is a small device made up of semiconductor material like germanium and silicon. c. IC was invented by Robert Noyce and Jack Kilby. d. Keyboards and monitors were developed during the period of first generation of the computers. e. CRAY –X-MP super computer was developed during the third generations of computer. 4. Match the following. Vacuum Tube Fourth generation Bio-Chips Microprocessor VLSI Fifth generation IBM PC Machine language First Generation First generation

30 New Gateway to Computer Science Book-8 5. Write down the full forms of the followings. FORTRAN , COBOL, IC , LSI , VLSI, AI 6. Write very short answer to the following questions. a. What was the memory unit of first generations of computer? b. Who was the inventor of Vacuum Tube? c. In which generation were FORTRAN and COBOL used as programming language? d. Name any two computers that were used in third generation. e. In which generation was IC used as the memory component? f. In which generation the concept of AI will be used? 7. Write short answer to the following questions. a. Name the various computer generations. b. List out the memory components used by different generation of computers. c. Write any two differences between the third and the fourth generation of computer. d. Write any four features of the second generation computer. e. What is Artificial Intelligence? Explain in short. 8. Write long answer to the following questions. a. Explain the features of the third and the fourth generation of computer. b. Explain the memory unit used by different computer generations with their time duration. c. Explain about third generations of computers with its features and examples. Project Work & Activity • Prepare a computer generation chart including their memory component, example and time duration. • Conduct a presentation programme about the computer generations in your class.

31 New Gateway to Computer Science Book-8 Introduction Computers are classified on the basis of their work, size brand and model. People are using different types of computers according to their requirement. The computers that are personally used for simple work may not be compatible to the business and for complex calculations. The computers that you are used at your home and the computers that are used for film animation and video editing are totally different. Next example we can take like the computer using at department store and the computer used at telecommunication office is totally different. The telecommunication office needs very high range of computer to work as compared to the computer that is used at department store. The types of computer are classified according to the purpose of uses such as special purpose and general purpose computer. Classification of computer The computer can be classified as below. On the basis of work/function On the basis of Size/ configuration On the basis of Brand On the basis of Model In this class, we are going to explain the types of computer on the basis of work and size only. Types of Computer 4 Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • identify the types of computers. • explain the features of each type of computers. • describe the types of personal/Desktop computers. Laptop / Notebook Computer and Handheld computer.

32 New Gateway to Computer Science Book-8 On the basis of work There are three types of computer on the basis of work they are analog, digital and hybrid computer which we are going to discuss below. Analog Computers Analog computers are used to process analog data. Analog data is continuous nature and which is not discrete or separate. Such type of data include temperature, pressure, speed, weight, voltage, depth, etc. Analog computers are the first developed computers which provide the basis for the development of the modern digital computers. The Speedometer of a car measures speed, the change of temperature is measured by a Thermometer, the weight is measured by Weighting machine are the examples of analog device. The computers which provide us with continuous information are called analog computer which represent physical quantities in the form of waves or in continuous form. Analog computers do not require any storage capability because they measure and compare quantities in a single operation. Output from an analog computer is generally in the form of readings on a series of dial or a graph on strip chart. Features of an analog computer The speed of an analog computer is high. These computers are not reliable and do not display actual data. These computers are the base for digital computers. These computers are difficult to operate and use. These computers are easy to develop. These computers have small storage capacity or no memory. Digital Computers The computers which present physical quantities with the help of symbols or numbers and provide us discrete information are called digital computers. A digital computer works with digits to represent numerals, letters or other special symbols. Digital Computers operate on inputs which are ON-OFF type and then output are also in the The Antikythera mechanism was an ancient Greek analog computer. CT-Scan stands for Computed Tomography Scan. Exploring Knowledge!

33 New Gateway to Computer Science Book-8 form of ON-OFF signal. Normally, an ON is represented by a 1 and an OFF is represented by a 0. So we can say that digital computers process information which is based on the presence of an electrical charge. A digital computer can be used to process numeric as well as non-numeric data. It can perform arithmetic operations like addition, subtraction, multiplication and division and also logical operations. Most of the computers available today are digital computers. Features of digital computer These computers are easy to use. These computers are reliable. These computers have large memory and storage capacity. Working speed of digital computers is slower as compared to analog computers. These computers are divided into different categories such as personal computers, Mainframe computers and Super computers. Hybrid Computers The computers which have qualities of both digital and analog computers are called hybrid computers. Hybrid computer has the speed of analog and the memory and accuracy of digital computer. A hybrid is a combination of digital and analog computers. It combines the best features of both types of computers. Hybrid computers are used mainly in specialized applications. The hybrid computer processes both continuous and discrete data. For example, a petrol pump contains a processor that converts fuel flow measurements into quantity and price values. In hospital Intensive Care Unit (ICU) an analog device is used which measures blood pressure and temperature which are then converted and displayed in the form of digits. Features of a hybrid computer It has the combined features of analog and digital computer. These computers are reliable and provide accurate result. These computers are fast and more reliable. It is mainly used in robotics. These are the special purpose computers. • Seymour Cray designed the first Super computer “CDC 6600” in 1964. CDC 6600 is known as the first Supercomputer. • Presently, China’s “Tianhe – 2” is the world’s faster Supercomputer. Exploring Knowledge!

34 New Gateway to Computer Science Book-8 There are three types of computers on the basis of work they are analog, digital and hybrid computer. Analog computers are used to process analog data. Analog computers do not require any storage capability because they measure and compare quantities in a single operation. ON is represented by a 1 and an OFF is represented by a 0. A digital computer can be used to process numeric as well as non-numeric data. A hybrid is a combination of digital and analog computers. The hybrid computer combines the best features of both analog and digital computer. The hybrid computer processes both continuous and discrete data. Quick Learn On the basis of size There are four types of computer on the basis of size. They are super, mainframe, mini and microcomputers which we are going to discuss below. Super computer Supercomputers are the most powerful computers in terms of performance and data processing. A supercomputer is a computer that has highest data processing and operational rate which is used for scientific and engineering applications. These are specialized computers used by large organizations. These computers are used for research and exploration purposes. On 29th July, 2015, President of the United States, Barack Obama, approved the development of an Exascale Super Computer. The examples of super computers are Cray XMP, CDC Cyber 2003, Cray -1, PARAM, etc. Uses of Supercomputers Space Exploration Earthquake studies Weather Forecasting Nuclear weapons testing

35 New Gateway to Computer Science Book-8 Mainframe computer Mainframe computers are not powerful as super computers, but they are quite expensive. Many large firms and government organizations use mainframes to run their business operations. Hundreds of users can work together with this computer system at a time. Mainframe computers are the fastest computers with large data storage capacity. It can also process and store large amount of data. Banks, educational institutions and even insurance companies use mainframe computers to store data about their customers, students and insurance policy holders. IBM 401, ICL 2950, IBM 7090 are the mainframe computers. Mainframe computers are ultra-high-performance computers made for high-volume, processor-intensive computing. They are typically used by large businesses and for scientific purposes. Minicomputer Minicomputers are used by small businesses and firms. Minicomputers are also called “Midrange Computers”. These are small machines and can be accommodated on a disk. These computers are not designed for a single user. Individual departments of a large company or organizations use mini-computers for specific purposes. For example, a production department can use mini-computers for monitoring certain production process.K-202, Texas Instrument TI-990, SDS-92, IBM Midrange computers are the popular mini-computers. A mini-computer is a type of computer that possesses most of the features and capabilities of a large computer but is smaller in physical size. There are four types of computer on the basis of size. They are super, mainframe, mini and microcomputers. Super computers are the most powerful computers in terms of performance and data processing. Supercomputers are specialized computers used by large organizations. Mainframe computers are not as powerful as supercomputers. Many large firms and government organizations use mainframes to run their business operations. Mainframe computers are the fastest computers with large data storage capacity. Minicomputers are used by small businesses and firms. Minicomputers are also called “Midrange Computers”. Quick Learn

36 New Gateway to Computer Science Book-8 Microcomputer The micro-computers are widely used and the fastest growing computers. Desktop, laptops, personal digital assistant (PDA), tablets and smartphones are the examples of microcomputer. These computers are the cheapest among the other three types of computers. These computers are specially designed for general proposes like entertainment, education and personal work. Dell, Apple, Samsung, Sony, Toshiba, etc. companies are producing various microcomputers these days. Desktop computers, Gaming consoles, Sound and Navigation system of a car, Netbooks, Notebooks, PDA’s, Tablet PC’s, Smartphones, Calculators are all type of Microcomputers. A microcomputer is a computer with a central processing unit (CPU) as a microprocessor designed for individual use; a microcomputer is smaller than a mainframe and a minicomputer. Here we are going to discuss about some microcomputers. Personal Computers/Desktop computers These are small size computers and are used by a single user. Desktop computers are also called personal computers or PC. We can use these computers easily in offices, colleges, schools, homes, and factories for various purposes. A desktop computer is a personal computer that fits on or under a desk. They usually consist of a monitor, keyboard, mouse and with a horizontal or vertical casing box. The casing contains the various computer units like hard disk, motherboard, RAM, ROM, Central Processing Unit, power switch, etc. Characteristics of desktop computers These computers have fast speed and accuracy. It is small in size and easy to move. It is very easy to operate. These computers are cheaper than other computers. We can use desktop computers in a singleuser and multi-user environment • The IBM 5100 is the first portable computer, which was released on September 1975AD. •The first portable computer or laptop is considered to be the Osborne I, which was released on April 1981 AD developed by Adam Osborne. • The first Apple laptop was the Macintosh Portable which was released on September 1989 AD. Exploring Knowledge!

37 New Gateway to Computer Science Book-8 Laptop / Notebook Computer Laptop computers are another category of personal computers. These computers are small in size and light packed in. These computers are moveable because they work on batteries and can operate without an external power source. Laptop computers are also called Notebook computers. DEL, HP, ACER, SAMSUNG, TOSHIBA, etc. are the popular laptop manufacturing companies. Laptop computer is a portable personal computer powered by a battery or an AC cord plugged into an electrical outlet. Handheld Computer A handheld computer is a portable computer that is small and can be held in one’s hand. Handheld computers have not replaced notebook computers because of their small keyboards and screens. Traditional hand-held computers were PDAs and devices specifically designed to provide PIM (personal information manager) functions, such as a calendar and address book. Today Pocket PCs, smartphones and tablets are common consumer devices. The handheld devices are turn into palmtop and pocket devices. Handheld computers are typically used for personal information manager (PIM) types of applications: maintaining schedules, keeping names and phone numbers, doing simple calculations like smartphones and tablets. The micro-computers are widely used and the fastest growing computers. Desktop, laptops, personal digital assistant (PDA), tablets and smartphones are the examples of microcomputer. Microcomputers are the cheapest among the other types of computers. The Micro-computers are specially designed for general proposes. A desktop computer is a personal computer that fits on or under a desk. Desktop computers are also called Personal computers or PC. Laptop computers are another category of personal computers. DEL, HP, ACER, SAMSUNG, TOSHIBA, etc. are the popular laptop and tablet manufacturing company. A hand-held computer is a portable computer that is small and can be held in one’s hand. Quick Learn

38 New Gateway to Computer Science Book-8 Steve Jobs, Steve Wozniak and Ronald Wayne are the founder of Apple Company which is located at USA. Intel 4004 was the First microprocessor. A tablet is a wireless, portable personal computer with a touch screen interface. Exploring Knowledge! 1. Choose the best answer from the given alternatives. a. Which of the following is a type of computer on the basis of work? i. Digital Computer ii. Super Computer iii. Notebook Computer b. Which of the following computers is used to process numeric as well as digital data? i. Digital Computer ii. Hybrid Computer iii. Analog Computer c. Which computer has the both of the features of analog and digital computer? i. Digital Computer ii. Hybrid Computer iii. Analog Computer d. Which of the following computer is called personal computer? i. Super Computer ii. Hybrid Computer iii. Micro Computer e. Which of the following is a mainframe computer? i. IBM 1401 ii. ICL 2950 iii. Both (i) and (ii) f. Which of the following is a Microcomputer? i. Laptop Computer ii. Mainframe Computer (iii) Super Computer 2. Fill in the blanks with suitable words. a. There are three types of computers on the basis of work they are …………, digital and ………… b. ……… is represented by a 1 and an ………… is represented by a 0. EXERCISE

39 New Gateway to Computer Science Book-8 c. A ……… computer can be used to process numeric as well as non-numeric data. d. …………… computer processes both continuous and discrete data. e. Many large firms and government organizations use ……………. to run their business operations. f. …………………… are used by small businesses and firms. g. …………… are the cheapest among the other types of computers. h. A ……………… is a personal computer that fits on or under a desk. i. Desktop computers are also called ……………….. 3. State whether the following statements are true or false. a. Analog computers are used to process digital data. b. A hybrid is a combination of digital and analog computers. c. There are two types of computer on the basis of size. d. Supercomputers are specialized computers used by large organizations. e. Mainframe computers are not as powerful as supercomputers. f. Mainframe computers are the fastest computers with large data storage capacity. g. Supercomputers are also called as “Midrange Computers”. h. Desktop, laptops, personal digital assistant (PDA), tablets and smartphones are the examples of analog device. i. The Micro-computers are specially designed for general proposes. j. Laptop computers are another category of personal computers. 4. Match the following. Super Computer Computer manufacturing company Mini Computer Personal Computer Analog Computer Used for highest data processing Laptop Computer SDS-92 DEL, HP Process analog data

40 New Gateway to Computer Science Book-8 5. Write down the full forms of the followings. ICU, PDA, PIM, PC 6. Write very short answer to the following questions. a. Name the computers on the basis of work. b. Which computer has the both combined features of analog and digital computer? c. Which computer can be used to process numeric as well as non-numeric data? d. Which device is used to measure blood pressure and temperatures these days? e. Write any two examples of mainframe computer. f. Name any two popular laptop manufacturing company. 7. Write short answer to the following questions. a. Define analog computer with any four features. b. Write down the features of digital and hybrid computer. c. What are the computers on the basis of size? Define any two of them. d. Write any four characteristics of desktop computers. e. Why are laptop and palmtop computers popular these days? 8. Write long answer to the following question. a. Define microcomputer. Explain the types of microcomputers in detail. Project Work & Activity Collect at least two pictures for the following devices and paste in a chart paper. Analog Computer , Digital Computer , Super Computer , Laptop Computer, Palmtop computer, Analog Thermometer, Digital thermometer, CT Scan machine, X-Ray Machine.

41 New Gateway to Computer Science Book-8 Introduction Computer hardware is the physical parts or components of a computer. Hardware includes internal and external components such as the monitor, keyboard, hard drive disk, mouse, printers, graphic cards, sound cards, memory, motherboard and chips. A computer needs both hardware and software to work. Computer software is a collection of computer programs which helps to give instructions to the computer system to perform some specific task. Anything that can be stored electronically is also computer software. Computer software is a set of instructions or statements that is carried out by the CPU of computer. Computer software is also called programs. Without programs, computers are useless. Types of computer hardware Input Hardware An input device is a piece of computer hardware equipment that is used to provide data and instructions to the computer system for processing. It is a device that translates data into a form the computer can process. Normally, it translates into binary code that can be processed by the computer to translate words, sounds, numbers, and images. The input computer hardware are keyboard, scanner, pointing devices, Joysticks, and others. Introduction to Computer 5 Hardware & Software Chapter This chapter covers the following topics: Expected Competency At the end of this unit, students will be able to: • describe the types of software . • explain the operating System and its functions. • write about language translator and its types. • tell the differences between compiler and interpreter. • identify utility software. • tell the types of application software.

42 New Gateway to Computer Science Book-8 Processing Hardware Processing hardware is responsible to process all the activities inside the computer from the data entering stage to output stage. The CPU of the computer is more responsible for this which is like a brain of human. It is the part of the computer that gives out all basic instructions to every other component on your computer. The CPU has the following three sections which are listed below. a. The arithmetic logic unit (ALU), which performs arithmetic and logical operations. b. The control unit (CU), which extracts instructions from memory and decodes and executes them. c. Registers/the Memory Unit, which is a temporary storage areas which are responsible for holding the data that is to be processed. Output Hardware Output hardware are mainly responsible for displaying the processed data which allow computers to communicate with users and with other devices. Output is the final result displayed after the processing, which is meaningful. The devices that are used to display the result to the user are output hardware. The output can be softcopy, hardcopy or even in audio or visual format. The monitor and printer are the commonly used output devices. The output displayed by the monitor is called softcopy output and the output displayed by the printer is called hardcopy output. The softcopy output is changeable and hardcopy output is not changeable. Primary and secondary Memory Computers are used not only for processing the data for immediate use, but also for storing a large volume of data for future use. In order to meet these two specific requirements, computers use two types of storage location; one is for storing the data that are being currently handled by the CPU and the other, for storing the results and the data for future use. The storage location where the data are held temporarily is referred to as the primary while the storage location where the programs and data are stored permanently for future use is referred to as the secondary memory. The primary memory is generally known as ‘Memory’ and the secondary memory as ‘storage’. Types of primary memory Random Access Memory (RAM): It is a volatile memory and losses all its data when the power is switched off. It is the main memory of the computer system that stores the data temporarily and allows the data to be accessed in any order. RAM is made up of different ICs, which are mounted on a printed circuit board. RAM is also known as read/write

43 New Gateway to Computer Science Book-8 memory because it can perform both read as well as write operations. The speed of RAM is faster than the other memory devices, such as hard disk, floppy disk, etc. Read Only Memory (ROM): It is the memory that stores the data permanently, i.e., it can retain the data even when the power of the computer system is switched off. The data can be easily read from this type of memory but cannot be changed. ROM is the most commonly used memory in devices such as calculators, printers, etc. ROM does not allow the random access of data rather it allows sequential access of data. It is less expensive as compared to RAM and other storage devices, such as magnetic disk. Secondary memory Secondary storage devices have large storage capacity, and they store data permanently. They can be both internal and external to the computer, and they include the hard disk, compact disk drive, USB storage device, etc. The secondary memories are also known as auxiliary storage media. Computer hardware is the physical parts or components of a computer. An input device is a piece of computer hardware equipment that is used to provide data and instructions to the computer system for processing. The CP U of the computer is more responsible for processing activities which is like a brain of human. The devices that are used to display the result to the user are output hardware. The storage location where the data are held temporarily is referred to as the primary memory. The storage location where the programs and data are stored permanently for future use is referred to as the secondary memory. Random Access Memory is a volatile memory and losses all its data when the power is switched off. Read Only Memory (ROM) is the memory that stores the data permanently, i.e., it can retain the data even when the power of the computer system is switched off. Secondary storage devices have large storage capacity, and they store data permanently. Quick Learn

44 New Gateway to Computer Science Book-8 Types of software The computer software is commonly known as computer programs which consists of all the instructions that tell the hardware how to perform a task. There are two types of computer software which we are going to discuss below. System software System software is software that is designed to control and work with computer hardware. It helps to activate the computer system and provide the operating environment for other application software. The primary work of system software is to control, integrate and manage the hardware components of the computer system. It provides an operating environment where user can work with various computer applications software. Types of system software In general, there are four types of system software such as operating system, language translator, device driver, etc. which we are gooing to discussed below. Operating System An operating system is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, the computer and the software programs will be useless. Operating system software helps to activate the computer system and provide them common platform to work. Windows 98, Windows XP, Windows 7, Windows 8, Linux, UNIX, etc. are popular name of operating system. Functions of Operating system There are many functions performed by the operating system but the main function is to provide the common interface between the user and the hardware. Some of the important functions of an operating systems are listed below. Memory Management It is an important function of operating system. The memory cannot be managed without operating system. Different programs and data execute in memory at one time. If there is no operating system, the programs may mix with each other and the system will not work properly. Booting It is the process of starting the computer operating systems to work. It checks the whole computer system and makes it ready to work. • Windows 1.0 was released on November 20, 1985, as the first version of the Microsoft Windows. • Windows 3.0, released in May 1990. Exploring Knowledge!

45 New Gateway to Computer Science Book-8 Process Management CPU can perform one task at one time. If there are many tasks; operating system decides which task should get the CPU at first. Storage Management Operating system controls all the storage operation means how the data or files will be stored in the computers and how the files will be accessed by the users. Data security Data are important parts of a computer system. The operating system protects the data stored on the computer from unauthorized use, modification or deletion. Computer software is a collection of computer programs. System software is software that is designed to control and work with the computer hardware. An operating system is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer and software program will be useless. Memory Management, Booting, Process Management, Storage Management, Data security etc. are the functions of an operating system. Quick Learn Language Translator The instructions given by the users are the high level language which cannot be understood by the machine. So it must be translated into commands to understand by the machine. A computer language translator is a program that translates a set of code written in one programming language into a functional equivalent of the code in another programming language. The following are the important roles of a language translator. Translating the high-level language program input into an equivalent machine language program. Providing diagnostic messages wherever the programmer violates specification of the high-level language program. • The full form of UNIX is Universal Net work Information Exchange • Shareware is a software that allows a user to try all or part of the program for free before buying it. Exploring Knowledge!

46 New Gateway to Computer Science Book-8 Types of language translator Compiler: Compiler is a translator which is used to convert programs in high-level language to low-level language. It translates the entire program and also reports the errors in source program encountered during the translation. Source Program Target Program Complier Error Massager Interpreter: It is a translator which is used to convert programs in high-level language to low-level language. An interpreter translates line by line and reports the error once it encountered during the translation process. It directly executes the operations specified in the source program when the input is given by the user. It gives better error diagnostics than a compiler. Assembler: An assembler is a translator which is used to translate the assembly language code into machine language code. Differences between compiler and interpreter Compiler Interpreter It performs the translation of a program as a whole. It performs statement by statement translation. Program execution is faster. Program execution is slower. It requires more memory as linking is needed. Memory usage is efficient as no intermediate object code is generated. Debugging is difficult. Debugging is easy. C, C++ uses the compilers. Python, BASIC, and Ruby use interpreters. Device Driver A device driver controls a particular type of device that is attached to your computer, such as a keyboard, mouse, pen drive, etc. A device driver is a small piece of software that tells the operating system and other software how to communicate with a piece of hardware.The driver program converts the more general input/output instructions of the operating system to messages that the device can understand.

47 New Gateway to Computer Science Book-8 • The first compiler was written by Grace Hopper, in 1952 AD. • The first autocode and its compiler were developed by AlickGlennie in 1952 AD. for the Mark I. • PL/C was a computer programming language developed at Cornell University in the early 1970s. Exploring Knowledge! A computer language translator is a program that translates a set of code written in one computer language into another. Compiler, assembler and interpreter are the types of language translator. The function of a language translator is to translate the high-level language into machine language. A compiler is a translator which is used to convert programs in high-level language to low-level language. An assembler is a translator which is used to translate the assembly language code into machine language code. A device driver controls a particular type of device that is attached to your computer system. A device driver is a small piece of software that tells the operating system and other software how to communicate with a piece of hardware. Quick Learn Utility Software An utility software is a special type of system software used to maximize the utility of the hardware devices and computer system. We can use utility software for scanning the hard disk, repair and maintenance of computer system and remove the viruses from the computer system. Utility software is a system software designed to help analyse, configure, optimize or maintain a computer. Antivirus, Backup software, clipboard, compression utility, debuggers; scandisk, and other toolkits are the examples of utility software. Application Software Application software is developed for the specific use. This software is developed using high level language. An application software is a set of one or more programs designed

48 New Gateway to Computer Science Book-8 to solve a specific problem of a specific task. This program directs a computer to solve a user-oriented problem, such as preparing bills, preparing marks ledger, etc. Types of application softwares An application software is classified into two types they are packaged software and tailored software. Packaged Software A packaged software is software that is often used together to perform similar functions, or includes similar features, as a set of software programs. It is readymade software developed for the general users to perform the particular task. Word Processing, Database Management, Graphics software package like adobe, multimedia software, etc. are the examples of packaged software. Customized Software A customized software is also known as tailor-made software. This type of software is specially developed for some specific organization or other user. Software of hospitals, department stores, bill processing, school management software, banking software, air ticket reservations, etc. are some customized software. Custom software is developed for a single customer that can accommodate customer’s particular preferences and expectations. The custom software is designed according to the needs of the user or an organization. Schools and colleges can use custom software to keep admission details of students. Custom software are also known as bespoke software. Exploring Knowledge! A utility software is special type of system software used to maximize the utility of the hardware devices and computer system. Antivirus, Backup software, Debugger, Scandisk, etc. are the name of popular utility software. An application software is developed for the specific use. A packaged Software and customize software are the types of application software. A custom software is also known as tailor-made software. Quick Learn

49 New Gateway to Computer Science Book-8 1. Choose the best answer from the given alternatives. a. Which of the following is input hardware? i. Keyboard ii. Monitor iii. Speaker b. Which of the following is a processing hardware? i. CPU ii. Printer iii. Scanner c. Which of the following is a volatile memory? i. RAM ii. ROM iii. Hard Disk d. Which of the following is a system software? i. Operating System ii. Application Package iii. Graphics Design e. Which of the following is an language translator? i. Compiler ii. Interpreter iii. Both (i) and (ii) f. Which of the following is application software? i. Packaged Software ii. Customized Software (iii) Both (i) and (ii) 2. Fill in the blanks with suitable words. a. An …………. device is a piece of computer hardware equipment that is used to provide data and instructions to the computer system. b. The devices that are used to display the result to the user are ……………. hardware. c. The storage location where the programs and data are stored permanently for future use is referred to as the ……………… memory. d. ………………. is the memory that stores the data permanently. e. An …………….. is a software program that enables the computer hardware to communicate and operate with the computer software. f. The function of …………… is to translate the high-level language into machine language. g. ………………. is a translator which is used to translate the assembly language code into machine language code. h. A …………. is a small piece of software that tells the operating system and other software how to communicate with a piece of hardware. i. Antivirus, Backup software, Debugger, Scandisk, etc. are the name of popular …………………... EXERCISE