Oasis Radiant Computer Science Grade 2 By Er. Shankar N. Adhikary
Oasis Radiant Computer Science Grade 2 Written by Er. Shankar N. Adhikary Layout Design: Image Graphics Chabahil, Kathmandu Publisher: Oasis Publication (P) Ltd. Anamnagar, Kathmandu Nepal Tel: 977-01-4224004 Fax : 01-4227718 Printed in Nepal © Publisher First edition 2017 Second edition 2018 Reprint: 2019
Oasis Radiant computer science Grade Two 3 S.No. Units Title Page No. 1. Unit 1 Introduction to Computer 5 2. Unit 2 Evolution of Computer 11 3. Unit 3 Types of Computers 18 4. Unit 4 Characteristics and Application of computer 25 5. Unit 5 Keyboard and Mouse 32 6. Unit 6 Computer Hardware, Software and Humanware 39 7. Unit 7 MS Paint 44 CONTENTS
Acknowledgement We are living in the 21st century. This is the age of Information and Communication Technology (ICT). ICT has become an integral part of our daily life. It facilities the business professionals, academicians, students, banking and other sectors. It has become a fundamental right of children to get computer education. They have to get the basic to advance knowledge of computer to cope the changes in future. The Government of Nepal has prescribed the syllabus and course outline for the computer education from primary to higher secondary level. Students are not able to get quality computer education due to the lack of quality text books and the limited access to the computer system in schools. To address this scenario, I have developed the complete series of computer book with name Oasis Radiant Computer Science from grade I to grade XII. I have devoted more time for the research and development for the preparation of this book. It provides a comprehensive and balanced coverage at the CDC syllabus. It is possible due to the comprehensive support of my colleges, family members, students and the teachers. I would like to acknowledge all who have directly or indirectly encouraged me to prepare this book. Specially, my thanks go to the students and teachers of different schools for their regular interactions and inspirations to prepare this book. In the same way my thanks go to my parents Tek Nath and Chisa Maya Adhikary, family members Lachhima Adhikary, Jagan Adhikary, Sarashwati Adhikary and lovely kids Samridhi, Sampada, Prasamsha, Ballavi, Ragavi, Suyash and Suyasha Adhikary for their valuable contribution to prepare this book. I must give thanks to OASIS PUBLICATION family for their innovative help to prepare and publish this book. Finally, all the suggestions and comments are acknowledged. Thanking all. Er. Shankar N Adhikary Tarkeshwor, Kathmandu [email protected]
Introduction to Computer 1 Chapter Describe Output devices What is a computer? Explain about the Input devices. What is CPU?
6 Oasis Radiant computer science Grade Two 1 Introduction to Computer UNIT Computer is an electronic device. It accepts data and instructions from the user by using input devices. It stores them and processes according to the instructions given by the user. Finally it gives the results to the user by using output devices. There are three sections of computer system. They are input section, processing section and output section. A typical computer system is shown in the figure below: Some components of the computer system are given in above figure. They are CPU, monitor, mouse, keyboard, printer and speakers. CPU(Central Processing Unit) It is the main part of the computer system. It is also known as the brain of the computer. It has three sections: Memory Unit, ALU (Arithmetic Logical Unit) and Control Unit. It is inside the CPU box which is called Monitor CD-ROM drive Printer Keyboard Speaker Mouse Floppy drive CPU box
Oasis Radiant computer science Grade Two 7 casing. Casing box has different buttons and drives like Floppy Drive, Digital Versatile Disk (DVD) drive and CD-ROM (Compact Disk Read Only Memory) drive as given in the figure. Monitor Monitor is popular visual output device. It displays the result on its screen. It is a TV like device. There are three types of monitors. They are CRT (Cathode Ray Tube) monitor, LCD (Liquid Crystal Display) and LED (Light Emission Diode) monitor. Mouse Mouse is a pointing type input device that helps to give input to the computer. It has three buttons: left , right and scroll button. There are mechanical and optical mouse. Keyboard Keyboard is a popular input device that helps to give text and numeric data to the computer system. It has different types of keys like alphabet keys, number keys, arrow keys and some special keys.
8 Oasis Radiant computer science Grade Two Printer Printer is a popular output device that gives the result by printing the document. It is a hard output device. There are different types of printers. They are: Laser printer, Dot-matrix printer, Inkjet printer etc. Speakers Speaker is an audio output device that gives the sound output. We can use it to listen to the music from the computer. There are different types of speakers connected to the computer system. Chapter Review • A computer is an electronic device. It accepts data and instructions from the user by using input devices. It stores them and process according to the instructions given by the user. • Casing box has different buttons and drives like Floppy Drive, Digital Versatile Disk (DVD) Drive and CD-ROM (Compact Disk Read Only Memory) Drive. • Three types of monitors are CRT (Cathode Ray Tube) monitor, LCD (Liquid Crystal Display) and LED (Light Emission Diode) monitor. • Mouse is a pointing type input device that helps to give input to the computer. • Keyboard is a popular input device that helps to give text and numeric data to the computer system.
Oasis Radiant computer science Grade Two 9 • Printer is a popular output device that gives the result by printing the document. It is a hard copy output device. • Speaker is an audio output device that gives the sound output. We can use it to listen to the music from the computer. 1) Who am I ? a) I am known as the brain of the computer. ......................................................................................... b) I am popular output device. I give output by printing it in paper. ......................................................................................... c) You can use me to listen music from the computer. ......................................................................................... d) I am a section of computer system, which gives you a meaningful output. ......................................................................................... e) I have different types of keys like alphabet keys, number keys and some special keys. ......................................................................................... f) I am a popular visual output device. ......................................................................................... g) I am a pointing device that helps to give input to the computer system. ......................................................................................... 2) Answer the following questions: a) What is a computer? b) Write the full forms of the following: i) LCD ii) CPU iii) CRT c) Name the types of mouse. Workshop
10 Oasis Radiant computer science Grade Two d) What are the sections of central processing unit? e) What is a printer? f) Write the types of printer. g) What is the CPU? h) What is the keyboard? i) Draw a well labeled diagram of the keyboard. 3) Name the following devices: 4) Complete the following a. M _ U _ E b. S _ E _ K _ R c. A _ PH _ _ ET d. P _ IN _ E _ e. CE _ TR _ L 5) Project Work a. Draw a well labeled diagram of a computer. b. List any ten devices related to the computer system.
Evolution of Computer 2 Chapter What are modern computers? Describe the history of computer What are mechanical computers? Who is the father of computer?
12 Oasis Radiant computer science Grade Two Evolution of Computer UNIT Development of computer started with the use of number system. Number system was developed by Hindu philosophers. They started the numbers 0 to 9 for counting. Other numbers are derived from these numbers. Development of computer has crossed three types of technologies. They are: • Mechanical computers, • Electromechanical computers, and • Modern electronic computers. 2
Oasis Radiant computer science Grade Two 13 Mechanical Computers Abacus It is the first calculating device. It works manually. It was developed by the Chinese 2,500 years ago. It has three parts. Upper part is heaven. Lower part is earth. Upper and lower parts are separated by mid bar. Napier’s Bone It is a manual device. English mathematician John Napier built this device for the purpose of multiplication in 1617 A D. So, it is known as Napier’s bone. Slide Rule English mathematician William Oughtred developed the slide rule in 1620. It consists of the fixed scale and one movable scale over the fixed scale. Heaven Mid bar Earth
14 Oasis Radiant computer science Grade Two Pascaline Blaise Pascal had developed a machine at the age of 19 in 1642. It could add and subtract the numbers. It is popular with the name of Pascaline. Analytical Engine Charles Babbage invented the first computer in 1823 AD. It was called a different engine. He is known as the father of computer.
Oasis Radiant computer science Grade Two 15 Modern Electronic Computer IBM (International Business Machine) company developed the first electronic computer. It was the first computer manufacturing company. Now a days, you can see different types of computers with different models. They are popular as Personal Computer (PC), Laptop Computer, Apple Macintosh Computer etc. Chapter Review • Development of computer started with the use of number system. • Abacus was developed by the Chinese 2,500 years ago. • English mathematician John Napier built a device for the purpose of multiplication in 1617 A D
16 Oasis Radiant computer science Grade Two Workshop • William Oughtred developed the slide rule in 1620. • Blaise Pascal had developed Pascaline at the age of 19 in 1642. • Charles Babbage invented the first computer in 1823 AD. • IBM (International Business Machine) company developed the first electronic computers. 1. Who am I ? a. I am the father of computer. ............................................................................................. b. I am the first calculating device. ............................................................................................. c. I am the inventor of Napier’s Bone. ............................................................................................. d. I invented the slide rule. ............................................................................................. e. I am the device invented by Blaise Pascal. ............................................................................................. f. I am the first computer manufacturing company. ............................................................................................. g. I am the lower part of Abacus. ............................................................................................. 2. Answer the following questions. a. Who is Charles Babbage? b. Name the three parts of abacus? c. Who invented the Slide Rule? d. For what purpose was Napier’s bone built?
Oasis Radiant computer science Grade Two 17 e. What was the use of Pascaline? f. Who invented difference and analytical engine? g. How old was Blaise Pascal when he invented Pascaline? h. Which is the first counting device? 3. Name the following devices: 4. Complete the following: a. P__ SCA __ I __ E b. N __ PI __ R c. M __ C __ N __ O __ H d. D __ V __ C __ S e. E __ E __ T __ O __ E __ H __ N __ C __ L f. B __ BB __ G __ 5) Project Work a. List any ten electronic and mechanical computers. b. Make a transformation chart from early computers to modern computers.
Types of Computers 3 Chapter Describe hybrid computer Describe analog computer Describe digital computer Describe desktop computer
Oasis Radiant computer science Grade Two 19 3 Types of Computers UNIT Computers are everywhere. We can see them at office, school, college, bank, hospital, etc. On the basis of the technology and working capacity, we can classify them into different types. Popular types are: analog, digital and hybrid computers. Analog Computer Computers that use the analog signal for their operation are analog computers. These computers are used in hospitals, air-crafts, telephone billing system, temperature recording, etc. An analog computer can be mechanical analog computer or electronic analog computer. Mechanical analog system Clock Telephone billing machine
20 Oasis Radiant computer science Grade Two Digital Clock Digital Computer Computers that use the digital signals for their operation are digital computers. They are very popular modern computers. They can perform calculations and logical operations using digits. There are three types of digital computers. They are desktop computers, laptop computers and tablets. a) Desktop Computers We use desktop computers at work, home, school, etc. They are small in size and usually sit on a top of the desk. So they are called desktop computers. They have CPU, monitor, mouse, keyboard. etc. as given in the figure. b) Laptop Computers Laptops are also personal computers. They are more advanced, smaller in size and easily portable than desktop computers. During the working time, we usually place these computers on the lap, so they are known as laptop computers.
Oasis Radiant computer science Grade Two 21 c) Tablet Computers Tablets are handheld computers. These are more portable than laptops. Instead of a keyboard or touchpad, tablets use a touchsensitive screen for typing and working with programs. The iPad is an example of a tablet. Hybrid Computers Computers that use both analog and digital signals for processing are the hybrid computers. They can process both analog and digital signal. Chapter Review • Popular types of computers are analog, digital and hybrid computers. • Computers that use the analog signal for their operation are analog computers. • Computers that use the digital signals for their operation are digital computers.
22 Oasis Radiant computer science Grade Two Workshop • There are three types of digital computers. These are Desktop computers, Laptop computers and tablets. • Computers that use both analog and digital signals for processing are the hybrid computers. • Tablets are handheld computers. They are more portable than laptops. • Laptops are also personal computers. They are more advanced, smaller in size and easily portable than desktop computers. • We use desktop computers at work, home and school for general purposes. 1. Who am I ? a. I use digital signals for my operation. .............................................................................................. b. I use analog signal for my operation. .............................................................................................. c. I am advanced, smaller and easily portable than desktop computer. .............................................................................................. d. I am a type of computer that uses both analog and digital signals for processing. .............................................................................................. e. I use touch-sensitive screen for typing and working with programs. ..............................................................................................
Oasis Radiant computer science Grade Two 23 2. Answer the following: a. What are digital computers? b. What are analog computers? c. What do you mean by hybrid computers? d. Name the types of digital computers. e. Where are analog computers used? f. List the parts of desktop computers. g. What are laptop computers? h. What are desktop computers? i. What are tablets? j. Draw a well labeled diagram of a tablet. 3. Name the type of following devices: Analog
24 Oasis Radiant computer science Grade Two 4. Complete the following: a. A __ A __ __ G b. D __ SK __ O __ c. L __ G __ C __ L d. H __ BR __ D e. T __ BL __ T 5. Project Work a. List the types of computer and the devices. S.N. Analog computers Digital computers Hybrid computers 1. 2. b. Write the model and types of computer available in your computer lab. Model: ............................................................. ............................................................. ............................................................. Types: ............................................................. ............................................................. .............................................................
Characteristics and Applications of Computer 4 Chapter List limitations of computer What are the application area of computer? List major characteristics of computer Write the working principle of computer
26 Oasis Radiant computer science Grade Two Characteristics and Applications of Computer 4 UNIT Applications of Computer Computer is an electronic device which can perform thousands of complex jobs within a fraction of second. They are used in different fields as given below: u They are used in hospitals. u They are used in schools and colleges. u They are used in publication houses.
Oasis Radiant computer science Grade Two 27 u They are used in banking and financial sectors. u They are used for entertainment. u They are used in design and development. u They are used in communication system. u They are used in research.
28 Oasis Radiant computer science Grade Two u They are used in weather forecasting. u They are used in online business. Limitations of Computer u Computer cannot think. u Computer is software dependent. u Computer cannot be used on the dusty environment. Characteristics of Computer ● Computer has very high speed of processing. It can work in a fraction of second like mili second, micro second, nano and pico second. ● Computer has very high storage. It has hard disk, DVDs, pen drives, etc. It can store huge amount of data in terms of GB (Giga Byte). ● Computer is a highly accurate device. If the inputs are correct, the output is also correct. ● Computers can perform different works. You can use the same computer for typing, playing games, doing online business etc. ● Computer never gets bored and is never tired. It can perform the same task with the same speed for a long time. It is called dilligence.
Oasis Radiant computer science Grade Two 29 Working Principle of Computer Computer receives the data and instructions as input from the input devices and these inputs are stored on the memory of the computer which are further processed in the ALU (Arithmetic-Logic Unit) to give desired output from the output device. The data processing cycle is given below. INPUT PROCESSING UNIT OUTPUT [Keyboard / Mouse] [CPU] [Monitor/Printer] Chapter Review • Computer is an electronic device that can perform thousands of complex jobs within a fraction of second. • Computer has very high speed of processing. It can work in a fraction of second like mili second, micro second, nano and pico second. • Computer is a highly accurate device. If the inputs are correct the output is also correct. • Computer never gets bored and is never tired. It can perform the same task with the same speed for a long time. • Computer receives the data and instructions as input from the input devices and these inputs are stored on the memory of the
30 Oasis Radiant computer science Grade Two Workshop 1. Who am I? a. I am used for communication system, online banking, weather forecasting, etc. ............................................................................................. b. Computers are dependent upon me. ............................................................................................. c. I am a device which can store high amount of data. I am found attached with computers. ............................................................................................. d. I am a unit in which input is further processed. ............................................................................................. e. I am a characteristic of a computer in which computer is never bored. ............................................................................................. 2. Answer the following: a. Write any three characteristics of computers. b. Write any three applications of computer. c. Write any three limitations of computer. d. Make the data processing cycle. computer which is further processed in the ALU (ArithmeticLogic Unit) to give desired output from the output device. • Computer cannot be used in the dusty environment. • Computer has a very high storage. It has the hard disk, DVDs, pen drives, etc. It can store huge amount of data in terms of GB (Giga Byte).
Oasis Radiant computer science Grade Two 31 e. Write the full form of ALU. f. Write the working principle of computer. 3. Name the application areas of following : 4. Complete the following: a. P __ O __ ES __ b. L __ G __ C c. F __ R __ AS __ I __ G d. B __ NK __ NG e. C __ C __ E 5. Project Work a. List any fifteen applications of computer. b. Paste the pictures of any five application areas of computer in your copy. Communication System
Keyboard and Mouse 5 Chapter Describe the mouse Describe keys of keyboard Write the functions of keyboard How to use mouse?
Oasis Radiant computer science Grade Two 33 5 Keyboard and Mouse UNIT Computer system has three sections. Input section, processing and storage section, and output section. Input section is the main section which is used to give data and instructions to the processing section of the computer. Keyboard It is a popular input device. You can give the data and instructions to the computer using the keyboard. The key on a keyboard lets you enter data and instructions into a computer. Function keys Alphabet keys Numeric pad Arrow keys Spacebar
34 Oasis Radiant computer science Grade Two Different Keys of Keyboard Escape Key You can press Esc to quit a task you are performing. Caps Lock and Shift Keys These keys let you enter text in uppercase (ABC) and lowercase (abc) letters. Press Caps Lock to change the case of all letters you type. Press the key again to return to the original case. Press Shift in combination with another key to type an uppercase letter. Ctrl and Alt Keys You can use the Ctrl (Control) or Alt (Alternate) key in combination with another key to perform a specific task. For example, in some programs you can press Ctrl and S to save a document. Spacebar You can press the Spacebar to insert a blank space. Function Keys These keys let you quickly perform specific tasks. For example, in many programs you can press F1 to display help information. Backspace Key You can press Backspace to remove the character to the left of the cursor. Enter Key You can press Enter to tell the computer to carry out a task. In a word processing program, press this key to start a new paragraph.
Oasis Radiant computer science Grade Two 35 Arrow Keys These keys let you move the cursor around the screen. Delete Key You can press Delete to remove the character to the right of the cursor. Numeric Keypad When the Num Lock light is on, you can use the number keys (0 through 9) to enter numbers. When the Num Lock light is off, you can use these keys to move the cursor around the screen. To turn the light on or off, press Num Lock. Mouse Mouse is a pointing type input device. It is used to select the required option from the menu. It has left, right and scroll buttons. Some activities done using the mouse are: Click Double click Right click Click and drag Scroll the button
36 Oasis Radiant computer science Grade Two Types of Mouse: Optical Mouse Rubber Ball Mouse Wireless Mouse Chapter Review • Computer system has three sections: input, processing and storage, and output section. • Keys on a keyboard let you enter data and instructions into a computer. • Caps Lock key lets you enter text in uppercase (ABC) and lowercase (abc) letters. Press Caps Lock to change the case of all letters you type. • Mouse is a pointing type input device. It is used to select the required option from the menu. • You can press the Spacebar to insert a blank space. • You can press Enter to tell the computer to carry out a task Workshop 1. Who am I? a. I am a key in the keyboard to insert a blank space. ..............................................................................................
Oasis Radiant computer science Grade Two 37 b. I am a button of mouse in between right and left buttons. .............................................................................................. c. I am a key to quit a task you are performing. .............................................................................................. d. I am a device that is used to point the required option from the menu. .............................................................................................. e. I am a device that is used to give text and numeric data to the computer. .............................................................................................. f. I am a key in the keyboard to remove the character to the right of the cursor. .............................................................................................. g. I am a key in the keyboard for quickly performing a specific task .............................................................................................. 2. Answer the following questions: a. What is the keyboard? b. What is the mouse? c. Name the three sections of computer? d. What is the use of arrow keys? e. Name different types of mouse? f. What is the use of Caps Lock key? g. Write the full forms of the following: i) CTRL ii) ALT
38 Oasis Radiant computer science Grade Two 3. Name the following devices: 4. Complete the following: a. K __ YP __ D b. O __ T __ C __ L c. W__ R __ L __ S __ d. SP__CE __ A __ e. E __ C __ P __ 5. Project Work • Draw a well labelled diagram of the mouse and keyboard. • Write the functions of the keys of the keyboard.
Computer Hardware, Software and Humanware 6 Chapter What is software? Describe computer system What is hardware? What is humanware?
40 Oasis Radiant computer science Grade Two Computer Hardware, Software and Humanware 6 UNIT Introduction The combination of different elements is called system. Computer system has different elements. It has three basic components. They are: • Hardware • Software • Humanware Hardware Physical parts of the computer are known as hardware. You can touch and feel these physical components. Hardware is the main body structure of the computer system. Hardware components of computer system are : mouse, keyboard, CPU, monitor, memory, etc.
Oasis Radiant computer science Grade Two 41 Software Computer software is the collection of programs. It is the application of computer in different fields. Software gives life to the computer system. We can get three types of software: systems software, application software and utility software. Humanware The relationship between the computer and the user is called humanware. The system is called the hardware and the application programs are called the software. To use the computer in different fields, user is required. The system where hardware, software and the user work together is called the humanware. Chapter Review • Computer has three components: hardware, software and humanware. • Physical parts of the computer are known as hardware. You can touch and feel these physical components. • Popular hardware components of the computer system are: mouse, keyboard, CPU, monitor, memory, etc.
42 Oasis Radiant computer science Grade Two Workshop • Computer software is all the application of the computer used in different fields. Software gives life to the computer system. • There are three types of software: systems software, application software and utility software. • The system where hardware, software, and the user work together is called the humanware. 1. Who am I? a. I am the collection of programs. ......................................................................................... b. I am the relationship between the computer and the user. ......................................................................................... c. I am the main body structure of computer system. ......................................................................................... d. I operate the computer. ......................................................................................... 2. Answer the following: a. What is hardware? b. What is software? c. What is humanware? d. Name any four computer hardware. e. Name different types of software.
Oasis Radiant computer science Grade Two 43 f. Name the elements of computer system. g. Write the use of the following: i) Hardware ii)Software iii) Human ware 3. Name the following devices: 4. Complete the following: a. H __ MA __ WA __ E b. C __ M __ O __ E __ T __ c. A __ P __ I __ A __ I __ N d. H __ RD __ A __ E e. M __ M __ R __ 5. Project Work a. List any five hardware components and write their uses. b. List any five software programs and write their applications. Windows System
MS Paint 7 Chapter How to draw figure? Describe the use of MS Paint Describe the tools of MS Paint How to handle the files in MS Paint?
Oasis Radiant computer science Grade Two 45 7 MS Paint UNIT MS Paint is a drawing program. It is available in Microsoft Windows system. It is a small graphic program. MS Paint program contains different tools and colors which are essential for drawing. Starting Paint You can start Paint in Windows7 using the following steps: Click on Start Menu Choose All Programs Choose Accessories Choose Paint
46 Oasis Radiant computer science Grade Two Or you can use the search line to start the Paint. Open the Start Menu Type mspaint.exe in the search line and press enter. You will get the system of Paint. Components of Paint Paint has the following parts in its working system. You can select the required tools, colors and the options for working with the Paint program.
Oasis Radiant computer science Grade Two 47 Ribbon Paint Button Home Tab
48 Oasis Radiant computer science Grade Two View Tabs Tools Panel Brushes Shapes
Oasis Radiant computer science Grade Two 49 Colour Palette Canvas Drawing Figures in Paint Paint is an accessory of Windows system. You can draw different types of geometrical shapes and make useful drawings using this program. You can select the required shape and color using the toolbars as given above.
50 Oasis Radiant computer science Grade Two Steps: Select the required tool from the tool box. Select the required color from color palette Click the mouse on the drawing canvas and draw the required figures. Saving a Paint File You can save the paint file using the following steps. Step 1: Click File→ Save or use the shortcut key, Ctrl+ S.