Computer Grade 4 - PDF Flipbook
Computer Grade 4
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Approved by: CDC/NG, Sanothimi, Bhaktapur, Nepal
School Level
COMPUTER SCIENCE Grade Author Kamal Bhattarai
Sunrise Publications Pvt. Ltd. Gyaneshwor, Kathmandu Phone: 01-4429376, 4423055
4
School Level
COMPUTER SCIENCE Grade
4
Publisher: Sunrise Publications Pvt. Ltd. !! Author: Edition: " +, - "
©
# $
Layout & Design
© All rights reserved with the Author, 2020 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means without the prior written permission of the author and publisher.
ISBN: 978-9937-530-07-1
Creation Graphics (Arun) %$& '( ) ) )*
Printed in Nepal
PREFACE We are living in the computer era. The 21st century is also called electronic century. Computer is one of the most powerful electronic machines. Computer has revolutionized the way we live and work. Computer has affected all aspects of peoples lives. It has become a need in our daily activities. In this century, computer has changed the style of our daily activities. In near future, we shall totally depend on the computer. For example, all library books will be converted into digital form. It will be possible to access library books through the internet. The online universal libraries will be developed for students and teachers. Similarly, the computer will control most of the systems. Our education will be incomplete without computer education. So, computer science is being the important subject in this modern world. Thinking this reality, Curriculum Development Centre (CDC) has included the computer science as the subject in the school level curriculum. A qualitative book plays important role to get perfect knowledge in any subject. We have published this series "Rising School Level Computer Science" realizing a need of a complete text book for school level students. "Rising School Level Computer Science" is a series of textbooks designed for primary to secondary level students to fulfill their special needs of conceptual and practical knowledge about computer science. This series has evolved out of the contributions from many teachers, students and authors, bringing together a variety of the creative ideas. The salient features: The series is based on a detailed syllabus of computer science that has been reviewed by many experts. Establishing clarity of thought and developing computer fluency is the main objective of this series. Each lesson focuses on specific concepts and associated skills. i.
They lay a strong foundation for learning computers.
ii. They contribute towards general intellectual development. iii. They are age appropriate. The series includes child friendly illustrations. The skills of critical thinking, collaboration, communication and creativity are addressed in the lesson content and activities that are highly relevent in the 21st century. The chapters have the chronological order of subject matters, than summarization, chapter exercises, and finally lab activities. Almost all the errors have been avoided in order to prevent students from wrong perception. Upto date information about computer science are also included. I would like to thank Mr. Arun Rimal for his creative layout and designing. I would also like to thank all the staffs of Sunrise Publications for their valuable suggestions and bringing out the book in this form. I would like to acknowledge all the teachers, students and other readers for their healthy comments and valuable suggestions in the formation of this series as a complete School Level textbook. At last, I am also thankful to all who are directly or indirectly involved in the preparation of this book. In spite of my best efforts, there may remain some printing and other errors in the book. So, I am always open for your healthy comments and valuable suggestions for the improvement of this series. Your comments and suggestions will surely find its place in upcoming editions. Thanks !
Author
Contents
1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 Chapter
An Introduction to Computer
5
Basic Parts of a Personal Computer
21
Input Devices
34
Processing Devices
51
Output Devices
62
The Correct Way of Operating a Computer 68 Concept of Operating System
80
Typing with Tux Typing
98
Word Processing Program : WordPad
62
Working Step-by-step
119
Introduction to LOGO program
125
Model Questions Computer Dictionary Full Forms
138 140 144
Chapter
1
AN INTRODUCTION TO COMPUTER Before You Read
-
Have you ever seen the computer? Can you name the places where you have seen the computer? What do you think the computer is used for? Why do you think people use computer in different fields? Do you have smart phone, tablet and laptop at your home?
We use different types of machines to perform different tasks in our daily life. Most of the machines we are using today are electronic machines such as calculator, television, mobile phone, camera, etc. Computer is also an electronic machine. Most of the machines can perform a single task but a computer can perform several tasks. A computer is playing the major role in our everyday life. Now-a-days computers are used in almost all the fields such as home, school, office, hospital, bank, shop, industry and so on.
What is Computer ? The term Computer is derived from the Latin word COMPUTARE, which means, to calculate. The name Computer was originally given to the people who had to do lots of calculations. The manually calculating job was very difficult and boring. Therefore, scientists always wanted to develop a machine that could perform calculations accurately and very fast. As a result of such thinking scientists developed a machine called ABACUS. It was the first calculating device in the world. A modern computer can be defined as: Rising School Level Computer Science, Grade -4
5
A
computer is an electronic machine that receives data and instruction as an input, processes the data according to the instructions, and produces meaningful information as a result. OR, A computer is an electronic machine that computes data and produces meaningful information. A computer has four basic parts. They are keyboard, mouse, system unit and monitor. These parts are shown in the following figure.
System Unit Monitor
Keyboard
Mouse
How does a computer work? A computer can perform several tasks. But a computer cannot perform the tasks itself. You have to tell the computer what to do by giving instructions. The pre-defined instructions that are stored in the computer are called programs. A computer processes the data by using these program instructions to produce result. Data are the input that you have given to the computer. 6
Rising School Level Computer Science, Grade -4
A computer works on the basis of Input, Process and Output principle. Input
Processing
Output
This is the basic working principle of all the computers.
What is Input- Process and Output? Most of the machines perform their work in three steps: Input, Process, and Output. Let us take an example: Working of a Refrigerator
Suppose you have to make some icecream from milk. The refrigerator follows these three main steps to perform this task: Step 1 : Input
First, you keep some milk in a refrigerator. Here the milk is the Input you give to the refrigerator.
Step 2: Process
Next, you close the refrigerator and switch on it. The refrigerator cools the milk. The cooling is the process that the refrigerator does. Step 3- Output
Finally, you will get icecream. The ice cream is the output you get from this process. The working principle of the refrigerator can be given as: Rising School Level Computer Science, Grade -4
7
Input Milk
Processing Cooling
Output Icecream
Working of a Computer
In the same way, a computer performs its task on the basis of Input, Process, and Output principle. Data
Input
Input:
Instructions
Processing
Output
You give any data and an instruction to a computer is called Input. You can give input to the computer through input devices such as, keyboard, mouse, joystick, scanner, web camera, etc.
Processing: The computer works on the data according to the given instructions. That is called processing. The processing is done by CPU (Central Processing Unit). Output:
A computer gives meaningful result after processing data which is called Output. A computer gives output through output devices such as monitor, printer, etc.
So, the working of a computer can be given as follows:
8
Rising School Level Computer Science, Grade -4
Input
Output
Process
Let us take an example,
To add the numbers 5, 7, 3 by using computer: Input
Data: 5 7 3
Output
Processing
5+7+3 Input
Output
5+7+3
15
Characteristics of a Computer A computer is not an ordinary machine, it is a smart machine. Computer is the most powerful machine because it has many special characteristics. Some of the specific features of computer that make it a smart machine are as follows: Rising School Level Computer Science, Grade -4
9
High Speed A computer can perform tasks very fast. It can perform billions of calculations in one second. The processing speed of a computer is measured in Mega Hertz (MHz) or Giga Hertz (GHz). Accuracy
Computer is an accurate machine. It does not make any mistake. However, its accuracy is totally depended on the given instructions and input data. If the data and instruction given to the computer are correct, it will always give correct result or output. If the input data is incorrect then the output will also be incorrect. Diligent Computer can continuously work for a long time without taking any rest. It can do the same task again and again (repeatedly) without loosing its speed and accuracy. So, it is called diligent machine. Versatile
A computer can perform different kinds of tasks one by one simultaneously. So, it is called versatile machine. It can perform several tasks such as calculations, drawing pictures, playing game, playing music, writing letters, sending e-mail, etc. 10
Rising School Level Computer Science, Grade -4
High Storage capacity
A computer has a high storage capacity. It can store large amount of data and programs permanently for future use. The stored data and programs are available any time for further use. Communication
A computer is used for communication. It is the most important feature of the computer. Now- a- days computer is mostly used to exchange messages through Internet all over the world. Through Internet, you can quickly receive or send information throughout the world. You can talk with people throughout the world by using computer and Internet.
Where are Computers used? Nowadays, computers are used in different fields. Some of the fields where computers are widely used are discussed below: Home
Computers at homes are used for the following purposes. To write letters and prepare documents. To draw different types of pictures. To use Internet and E-mails. Rising School Level Computer Science, Grade -4
11
Shop
Hospital
Bank
Uses of computer in different fields
Office
School
Library
School
Computers at schools are used for the following purposes. To keep records of students and teachers. To prepare exam papers and results. To prepare fee bills and salary sheets. Office
Computers at office are used for the following purposes. To prepare different types of documents. To keep employees' records. To maintain account ledgers. Hospital Computers at hospitals are used for the following purposes. To keep the records of patients and staff. To perform various clinical tests. To find out the diseases of patients and treat them. 12
Rising School Level Computer Science, Grade -4
Bank Computers at banks are used for the following purposes. To keep records of customers and staff. To provide ATM facility. To maintain account of customers. Library Computers at libraries are used for the following purposes. To keep records of books. To calculate fine and other charges. To search books available in the library. Shop Computers at shops are used for the following purposes. To keep records of goods. To prepare bills. To check stock.
Limitation of Computer Computers are useful machines with huge capabilities but have some limitations. The computer can only perform the tasks you instruct it to do. A computer cannot generate information by itself. If you give the computer wrong data, it is going to give you wrong information. Computer is unable to correct wrong instructions. Computer cannot take decisions itself. Rising School Level Computer Science, Grade -4
13
Important Points to Remember Computer is an electronic machine that processes raw data and gives meaningful information. The name Computer is derived from the Latin word COMPUTARE which means to Calculate. Input Process Output is the basic working principle of a computer. Some of the special characteristics of a computer are: fast work, accurate result, high storage capacity, diligence, etc. Now-a-days computers are used everywhere such as home, school, college, office, bank, library, hospital, etc.
Exercises 1.
Fill in the blanks with the given words from the box below.
Process raw data
14
computare
processing speed
CPU
a.
A computer is an electronic machine that processes ..
...........
and gives result.
b.
The name 'computer' is derived from the Latin word ..
...................
c.
Input ......................... and output is the basic working principle of a computer.
d.
The processing is done by ..
....................
e.
The time taken by a computer to process the data is called .......................
Rising School Level Computer Science, Grade -4
2.
3.
Write the characteristics of a computer in a single word.
a.
A computer never gets tired or bored while working for a long time ..
....................
b.
A computer does not make any mistake ....
....................
c.
A computer can perform billions of calculations in a second. ..
.....................
d.
A computer can perform several tasks such as drawing pictures, playing games, etc.
Answer the following questions.
a.
Write any four electronic machines that we use in our daily life. Ans: .........................................................................................................
b.
.................................................................................................................. What is computer? Ans: .........................................................................................................
c.
.................................................................................................................. Which was the first calculating device in the world? Ans: .........................................................................................................
d.
.................................................................................................................. What are the four basic parts of a computer? Ans: .........................................................................................................
e.
.................................................................................................................. What is the basic working principle of a computer? Ans: ......................................................................................................... .................................................................................................................. Rising School Level Computer Science, Grade -4
15
f.
Write down any four characteristics of a computer. Ans: .........................................................................................................
g.
.................................................................................................................. List any four places where computers are used. Ans: ......................................................................................................... ..................................................................................................................
h.
Why are computers called accurate machine ? Ans: ......................................................................................................... ..................................................................................................................
i.
Why are computers called versatile machine ? Ans: ......................................................................................................... ..................................................................................................................
4.
Write full form of the following.
a. 5.
b. ATM
c. MHz
d. GHz
State whether the following statements are true or false:
a. b. c. d. e. f. 16
CPU
The word 'computer' is derived from Latin word 'Computer'. Computer can perform only one task. Mouse, keyboard, monitor and system unit are the major parts of a computer. Predefined instructions stored in computer are called programs. Computer is very slow in processing. Computer produces correct output even if we input the wrong data.
Rising School Level Computer Science, Grade -4
6.
Write the technical terms for the following:
i. ii. iii. iv. 7.
The error in computer due to wrong input . ............................. The processed data. ............................... Continuous working capability of computer. ............................... The characteristics of computer that tells it can perform different task is. ...............................
Choose the best answer:
a.
b.
The major component of computer is i. Mouse
ii. Keyboard/ mouse
iii. System unit
iv. All of the above
The basic working principle of computer is ................ i. Input ii. Process iii. Output
c.
d.
e.
f.
iv. All of the above
The input devices of computer are ................ i. Monitor
ii. Keyboard
iii. Mouse
iv. Both (ii) and (iii)
The action taken on data to get information is called................ i. Processing
ii. Input
iii. Output
iv. All of the above
The error due to wrong input is ................ i. IGOG
ii.
OIGG
iii. GOIG
iv.
GIGO
The repeatedly working capacity of computer is ................ i. Accuracy
ii. Diligens
iii. Versatility
iv. Storage Rising School Level Computer Science, Grade -4
17
8.
Match the following.
Group A a. Keyboard b. IPO c. Set of instructions d. Processing e. Versatile
9.
Find the computer related words from the following.
L A L O T Z
1. 2. 3. 4.
18
Group B Working principle of computer Action taken on data Input device Characteristics of computer Program Information
O U T P U T
B O N R U B
C O D O M A
A D F C G J
N I H E T N
M O U S E K
O A N S J E
N R D I P Y
I E A N S B
T J T G O O
O N A G Z A
R K M O O R
P D F C S D
Project Work Draw a picture of computer and label its four basic parts. Make a chart to explain different characteristics of a computer. Draw a picture to show input, process and output for making a glass of juice. Write down input, process and output to multiply two numbers i.e. 5 and 10.
Rising School Level Computer Science, Grade -4
Class : 4 Time: 40 Min. 1.
2.
Unit Test Computer science
F.M.: 20 P.M.: 8
Answer the following questions:
a.
What is computer?
b.
Which principle does computer follow to work ?
c.
List any four basic part of computer.
d.
Why are computers called accurate machines ?
e.
Write any two limitations of computer?
f.
List any two places where computers are used.
Choose the best answer:
6×1=6
0.5×4 = 2
a.
The major components of computers are_______ i. Mouse ii. Keyboard iii. System unit iv. All of the above
b.
The error due to wrong input is______ i. IGOG ii. GOGI iii. OGIG iv. GIGO
c.
The device that processes data is_____ i. Keyboard ii. Monitor iii. CPU iv. None of the above
d.
Computers can be used in different fields because _______ i. They are accurate ii. They are versatile iii. They are diligent iv. All of the above Rising School Level Computer Science, Grade -4
19
3.
4.
Match the following: 0.5 × 4 = 2
Accuracy
(d) (c)
Action taken on data
c.
Processing
(b)
Feature of computer
d.
Information
(a)
Error due to wrong input
()
Input device
a.
GIGO
b.
Processed data
State whether the following statements are true or false: 0.5 ×4 = 2
i.
Computer always produces wrong output. False
ii.
Computer can be used in different fields. True iii. The set of instructions is called a program. True iv. Monitor displays the output. True 5.
Write the technical terms for the following:
0.5 × 4 = 2
i.
The processed data. Informations
ii.
Continuous working capability of computer. Diligence
iii. The set of instructions. Program iv. The data and instructions given to the computer. Input 6.
Write the full forms of the following:
a. 7.
20
CPU
b. ATM
c. MHz
Write short notes on:
a.
Uses of computer in office
b.
Versatility
Rising School Level Computer Science, Grade -4
0.5 ×4 = 2
d. GHz 2×2=4
Chapter
2
BASIC PARTS OF A PERSONAL COMPUTER Before You Read
-
Do you have laptop at your home? Which device works as mouse in laptop? Do you know why are mouse and keyboard used for? Do you find any differences between laptop and desktop computer?
A small computer that is designed for one person to use at work or at home is called personal computer or PC. Nowadays, computers are available in different shapes and sizes. The two common types of personal computer are: 1. Desktop computer 2. Laptop computer These two types of personal computers (PC) are most widely used in today's world.
Desktop Computer Desktop computers are the most commonly used computers all over the world. These computers are used everywhere such as at home, school, office, shop, bank, etc. This type of computers are bigger and heavier than laptop computers. So, they cannot be easily carried around. In this type of computer, the keyboard, mouse, monitor and system unit come separately. Rising School Level Computer Science, Grade -4
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Laptop Computer Laptop computers are small in size and lightweight computers. These computers can be used on the lap. So, they are named as laptop computers. Laptop computers can be easily carried from one place to another. These computers run on batteries. In this type of computer, the keyboard, touchpad, monitor and system unit are attached. These computers have built-in keyboard and built- in trackball as pointing device. Laptop computers are more expensive than desktop computers.
Basic Parts of Computer The system unit, monitor, keyboard, mouse, touchpad, speaker, AC (Alternet Current) adaptor and power cord are known as the basic parts of a computer. Some parts are different between desktop computer and laptop. All of the basic parts of a desktop and laptop computer are considered as computer hardware. Beyond these basic parts, there are other hardware parts that are located inside the computer case. Some peripheral devices such as printer, scanner, webcam, etc. are also connected to make the computer system more useful. Basic Parts of the Desktop Computer
The basic parts of the desktop computer are System Unit (also called computer case), Monitor, Keyboard, Mouse and Power Cord. These are 22
Rising School Level Computer Science, Grade -4
the parts you can notice right away when you look at a desktop computer.
Monitor
System Unit
Mouse Keyboard
Monitor Monitor is an output device of the computer. It is also called the Visual Display Unit (VDU). It shows the processed result of the computer. A monitor has an on/ off button and different control buttons. A monitor is connected to the system unit with a wire. It is a soft copy output device. Keyboard Keyboard is an input device of the computer. It is used to input data and instructions into the computer. A keyboard is connected to the mother board with a wire.
Keyboard consists of different keys like: a. Alphabet b. Number c. Other special keys It converts data and instruction in the form the computer can understand. Rising School Level Computer Science, Grade -4
23
Mouse
Mouse is also an input device of the computer. It is used to point objects on the monitor. With the help of mouse, you can give command to the computer. It is palm sized input device that is rolled on the flat surface to control an arrow-like structure on the monitor. System unit (Computer Case)
The system unit is also called computer case or CPU tower. It is a big box that contains the main components of the computer system. Motherboard, Hard disk, and other more devices are contained in this box. At the front and back side of system unit, you can see number of buttons, sockets and slots. The buttons, slots and sockets vary from computer to computer. However, the basic buttons, slots and sockets are similar in most of the desktop computers. Front view
Back view
Power cord
The power cord is the link between the power outlet and the power supply unit in the computer casing. If the power cord is not plugged into the computer, the computer will not power on. Power cord is also used to supply power to the monitor and other peripheral devices such as speaker, printer, scanner, etc. 24
Rising School Level Computer Science, Grade -4
Basic parts of Laptop Computer The parts of laptop computers are basically the same as desktop but they are smaller in comparison to desktop computer. The basic parts of laptop computers are monitor, keyboard, touchpad, casing, speaker, battery and AC adaptor. Those are explained below in brief. Laptop is a portable computer because it can be easily carried from one place to another. It can be used there where there is no electricity because it has a battery that supplies backup power to it. Screen Keyboard
Touch pad Casing
i.
Monitor/ Screen: It is a basic output device like desktop monitor which displays output of the computer.
ii.
Keyboard: It is a basic input device. Like desktop keyboard, it is used to input data and instruction into the computer. iii. Speaker: The laptop speakers are usually small and built into the screen or the body of the laptop. The speakers produce audio (sound) output. iv. Touchpad: It is also known as a track pad. It is a substitute for the mouse of the desktop computer. Its function is same as the desktop mouse. Rising School Level Computer Science, Grade -4
25
The buttons below the touchpad operate like the left and right mouse buttons. v.
Laptop Battery: Battery gives the power to the laptop. With the help of a battery, the laptop works about 2-6 hours without receiving power from the power adaptor.
vi. AC Adaptor: It is the source of electric power for a laptop. It supplies power to the laptop and charges the battery. vii. Casing: It is the body of the laptop inside which all the main components of the laptop are contained. It is like a desktop computer case. Motherboard, CPU, Hard disk, RAM (Random Access Memory) and other devices are contained inside casing.
How to use Touchpad in the laptop computer? To move the pointer on the screen, move your finger on the touchpad. To select an object on the screen, press left button once with your index finger and then release it. To drag objects on the screen, press and hold down the left button with your index finger and move another finger on the touchpad. When the object is moved in the required location release the left button. To double-click, rapidly press and release the left button twice with your index finger. To right-click, press and release the right button with your middle finger. 26
Rising School Level Computer Science, Grade -4
Important Points to Remember Personal computer is designed for one person to work at home or office. A Desktop computer is a Personal Computer designed to fit on a desktop. A Laptop computer is also a Personal Computer designed for mobile use. All the physical parts of the desktop computer and laptop computer are called hardware. The basic parts of the Desktop computer are computer case, monitor, keyboard, mouse and power cord. The basic parts of the Laptop computer are Monitor, Keyboard, Touch pad, Speaker, Battery, AC Adaptor and Casing. Keyboard is a primary input device that is used to input text as well as numbers into the computer. Mouse is a palm sized input device with two or more clicking buttons at its top. Monitor is a soft copy output device. The touchpad in a laptop is a substitute for the mouse of the desktop computer. The power cord is the link between the power outlet and the power supply unit in the computer casing.
Rising School Level Computer Science, Grade -4
27
Exercises 1.
2.
28
Read the clues and answer the question ''who am I?''
a.
I am bigger and heavier than a laptop computer .............................
b.
I am a small sized computer and I can run on batteries. .........................
c.
I show the processed result of the computer. .............................
d.
I supply electricity into the computer.
.............................
e.
I give commands to the computer.
.............................
Put a tick (
) in the correct option.
a.
What is a laptop computer? i. A personal computer designed to fit on desktop. ii. A personal computer designed for mobile use.
b.
What is the function of the touchpad? i. Same as mouse ii. Same as keyboard
c.
What is the function of AC Adapter? i. To supply power to the laptop ii. To charge the battery
d.
How to select objects by using touchpad? i. By pressing left button once ii. By pressing right button once
e.
The device that displays result and data for the user is ...... i. Monitor ii. Mouse iii. Keyboard iv. All of the above
Rising School Level Computer Science, Grade -4
3.
f.
The computer that can be easily carried from one place to another place is ........... i. Desktop computer ii. Laptop computer iii. Both (i) and (ii) iv. None of the above
g.
Keyboard consists of the keys like .............. i. Alphabet ii. Number iii. Special symbols iv. All of the above
h.
The wire that is plugged into power socket to supply power to the computer is .............. i. Mouse wire ii. Power cord iii. Keyboard wire iv. None of the above
Answer the following questions.
a.
What is a personal computer or PC? Ans: ......................................................................................................... ..................................................................................................................
b.
What are two common types of personal computers? Ans: ......................................................................................................... ..................................................................................................................
c.
What is a desktop computer? Ans: ......................................................................................................... ..................................................................................................................
d.
What is a laptop computer? Ans: ......................................................................................................... .................................................................................................................. Rising School Level Computer Science, Grade -4
29
e.
f.
4.
Write the full forms of:
a. 5.
6.
PC
b. VDU
c. RAM
d. AC
e. CPU
State true or false:
a.
Most commonly used computers are desktop computers.
b.
Laptop computer cannot be used there where there is no electricity.
c.
Mouse is used to control an arrow-like structure on the monitor.
d.
AC adaptor is source of power to the laptop computer.
e.
Speaker produces audio output.
f.
The function of touchpad and mouse is same.
Write the technical terms for the following:
a. b. c. d. 30
Write any two differences between the desktop computer and laptop computer. Ans: ......................................................................................................... .................................................................................................................. What are the basic parts of laptop computers? Ans: ......................................................................................................... ..................................................................................................................
The computers that are defined to fit on a desk. ............................................... The portable computers that can be used anywhere in any time. ............................................... The soft copy output device of computer. ............................................... The device that is used to give data in computer in the form of text. ...............................................
Rising School Level Computer Science, Grade -4
e.
The device that is used to point object on the screen. ...............................................
f. 6.
The big box that contains the major components of the computer. ...............................................
Match the following.
Group A a. Desktop computer
Group B Interface between power supply and devices Computer casing Lighter and expensive Heavier and cheaper
b. Laptop computer c. System unit d. Power cord 7.
Complete the following crossword. C S N G
T C R E E N
T O U
P L A
C L
M P U E
8.
Draw a complete picture of computer and label its parts.
LAB ACTIVITIES
1. 2. 3.
Go to the computer lab then observe the different parts of desktop and laptop computer. Practise for using the keyboard and mouse of a desktop computer and the touchpad of the laptop computer with the help of your teacher. Write the difference between Desktop and Laptop computer with suitable diagram in chart paper and patch on your computer lab. Rising School Level Computer Science, Grade -4
31
Class : 4 Time: 40 Min. 1.
2.
3.
4.
32
Unit Test Computer science
Answer the following questions:
F.M.: 20 P.M.: 8 6×1=6
a.
What is desktop computer?
b.
Write any two differences between desktop and laptop computer.
c.
What is monitor?
d.
What is keyboard?
e.
What is touchpad?
f.
What is system unit?
Match the following:
0.5×4=2
a.
Laptop
( ) Link between the power outlet and the power supply unit.
b.
Keyboard
( ) Can be used anywhere and anytime
c.
Mouse
( ) Used to input alphabet and numbers
d.
Power cord
( ) Palm sized pointing device
Write the technical terms for the following:
0.5×4=2
a.
The device that shows the processed result.
b.
Box that contains the major components of the computer system.
c.
The devices surrounding the CPU.
d.
Source of electric power for a laptop.
State true or false:
0.5×4=2
a.
Battery gives the backup power to the laptop.
b.
To move the pointer on the screen we should move our finger on the keyboard of laptop.
Rising School Level Computer Science, Grade -4
5.
6.
c.
Pressing and releasing the button of mouse is called clicking.
d.
The function of mouse and touchpad is different.
Fill the gaps with appropriate word(s):
a.
_______ is used to input data and instruction into the computer.
b.
The arrow-like structure moves on the screen when we move ________ .
c.
The system unit is also called _________ case.
d.
Speaker produces __________output.
Write the full form of the following:
a. 7.
0.5×4=2
CPU
b. PC
Write short note on:
a.
AC adaptor
b.
Touchpad
c. VDU
0.5×4=2
d. RAM 2×2=4
Rising School Level Computer Science, Grade -4
33
Chapter
INPUT DEVICES
3
Before You Read -
What is computer hardware? Have you seen mouse and keyboard? Have you ever played games in computer by using joysticks? Have you seen web camera? How many types of keys are there in keyboard?
Hardware The physical and mechanical parts of the computer that we can see, feel and touch are the computer hardware. There are three types of hardware which you are going to learn in coming units. a. b. c. d.
Input device or hardware (Mouse, Keyboard, Joysticks etc.) Processing hardware or devices CPU and its sections. Output hardware: Monitor, printer, speaker etc. Storage device: hard disk, pen drive, CD, DVD etc.
Input device or hardware A computer takes data and instructions as an input. The devices that are used to give input to the computer are called input devices. You can give instruction to the computer with the help of the input devices. Without the input devices, it is not possible to operate a computer. Different types of input devices are used in the computer. The most commonly used input devices are Keyboard and Mouse.
Keyboard 34
Rising School Level Computer Science, Grade -4
Mouse
Some of the commonly used input devices are as given below: 1. Keyboard 2. Mouse 3. Touchpad 4. Touch screen 5. Scanner 6. Joystick 7. Web Camera 8. Microphone Keyboard Keyboard is a basic input device of a computer. You can enter data and instructions into a computer by using the keyboard. There are different keys on the keyboard which perform different functions. There are near about 104 keys on a normal keyboard. On the basis of their function, the keys on the keyboard can be divided into five different groups. They are: i. Alphanumeric keys iii. Navigation keys
ii. Control keys iv. Numeric keypad
Function Keys
Control Keys Special Keys
Key Group
Alphanumeric keys
Typing keys
Navigation Keys
Key Indicator
Arrow Keys Numerical Keypad
Description These keys include the letters (alphabet), number and special character keys. There are 26 alphabet keys from a - z and 10 number keys from 0 to 9. The special keys are located at the upper half of the number keys. To type these characters, hold down the Shift key and press the character key. Rising School Level Computer Science, Grade -4
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Control keys
These keys include the CTRL, ALT, the Windows logo key and ESC keys. These keys are used alone or in combination with other keys to perform special functions in the computer.
Function keys
These keys include F1, F2, F3, and so on, up to F12. The function keys are used to perform specific tasks in the computer. The functions of these keys differ from program to program.
Navigation keys
These keys include the Arrow keys, HOME, END, PAGE UP, PAGE DOWN, and INSERT keys. These keys are used for moving around in documents. The arrow keys are used to move the cursor in the document.
Numeric keypad
There are 0 to 9 numbers in the numeric keypad. From The numeric keypad, you can type numbers quickly. To use these keys you have to press the Num Lock key.
Some Special Keys Besides these, some special keys, which are used while preparing the documents, are described below: Keys
Delete key 36
Description
The Delete key is used to remove the things such as letter, word or sentence from the
Rising School Level Computer Science, Grade -4
Keys
Description
document. When you do any mistake, you can remove that mistake by using the Delete key. When you press the delete key, it erases the letter to the right of the cursor. Backspace key
The Backspace key also erases the letter, word or sentence from the document. When you press the backspace key, it erases the letter to the left of the cursor.
Spacebar key
It is the largest key in the keyboard. This key is used to put a blank space between letters, numbers or words.
Enter key
This key is used to move the cursor to the next line before reaching the end of the current line. The enter key is also used to confirm the given instruction to the computer. After giving any instruction to the computer, you can press the Enter key.
Shift key
You can see two shift keys on your keyboard. This key is used in combination with other keys for different purposes. It is used to type in capital letters. And it is also used to type special characters. The special characters means the upper characters on the number keys and the punctuation keys. Hold down the shift key and then press the alphabet keys, the letters you type will be shown in capital letters. Rising School Level Computer Science, Grade -4
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To type the special characters like ~ ! @ # $ % ^ & * ( ) _ + | hold down the shift key and then press that character key. The special characters are located on the upper half of the number keys. Caps lock key
The caps lock key is used to type all the letters in capital or upper case. When the caps lock key is on, an indicator light appears on the upper right corner of the keyboard. You can turn off the caps lock key by pressing it again.
Mouse Mouse is a basic input device. It is also called the pointing device. It is used to point objects on the screen and give commands to the computer. When you move the mouse on the mouse pad, the mouse pointer on the monitor screen moves in the corresponding direction. Generally, a mouse contains three buttons: left button, right button and a scroll wheel. Scrool button Right mouse button Left mouse button
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Different buttons have different functions depending on the running program. This scroll wheel is used for many purposes such as scrolling through the long documents and long pages in web sites, to zoom in and out etc. To scroll down, roll the wheel backward (toward you) and to scroll up, roll the wheel forward (away from you). Holding and Moving the Mouse
Place your mouse beside your keyboard on the mouse pad. Hold the mouse gently with your index finger resting on the left button and your thumb resting on the side. To move the mouse, slide it slowly in any direction. As you move the mouse, a pointer moves in the same direction on your monitor screen. Mouse Actions
The mouse is used to give instructions to the computer. A computer performs tasks according to the given instructions. You can give instruction to the computer by using different mouse actions. Basically there are five mouse actions. They are as follows: i. Pointing ii. Clicking (single-clicking) iii. Double clicking iv. Right-Clicking v. Dragging
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Action
Description
Pointing
Moving the mouse pointer to point to any item on the monitor screen is called pointing. To point any item, move your mouse so the pointer appears to be touching that item. When you point to any item, a small box often appears to describe that item.
Clicking
Pressing the left mouse button once and releasing it is called clicking. The clicking is sometimes called single-clicking or left-clicking. To click an item, point to the item on the screen, and then press and release the left mouse button. Clicking is most often used to select an item or open a menu in the computer.
Click
Double-Clicking Click Click
Right-Clicking
40
Pressing the left mouse button twice quickly and releasing is called double clicking. To double-click an item, point to the item and then press left button twice quickly. Double-clicking is most often used to open items (files, folders or programs) on the computer. For example, you can start a program or open a folder or file by double-clicking its icon on the desktop. Pressing the right mouse button once and releasing it is called right clicking. To right-click an item, point to the item and then press and release the right mouse button. Right-clicking an item usually displays a list of commands you can do with the item. For example, when you right-click the Computer icon on your desktop, it displays a menu allowing you to open it, manage it, delete it, rename it, or see its properties.
Rising School Level Computer Science, Grade -4
Dragging
Moving the mouse while keeping the left mouse button pressed is called dragging. You can move items around your screen by dragging them. To drag an object: Ø Point to the object on the screen that you want to move. Ø Press and hold the left mouse button. Ø Move the object to a new location, and then release the mouse button. Dragging is also called dragging and dropping. Dragging is most often used to move files and folders from one location to another location.
Touch Pad
It is a touch sensitive pad that is used as a pointing device. By putting your fingers on the touch pad, you can point the objects and give commands to the computer. It is mostly used in some portable computers such as Laptop computer, palm top computer, Notebook computer, etc. Touch Screen
It is a touch sensitive screen. You can use your fingers to select objects on the monitor screen and give commands to the computer. In this screen, you can use your fingers instead of mouse. It replaces the use of mouse and light pen as a pointing device. Touch screens are mostly used on portable computers such as Laptop computer, Palm top computer, Note book computer, etc. Rising School Level Computer Science, Grade -4
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Joystick
Joystick is an input device. It is often used to play computer games. You can give commands to the computer by moving it. It has one or more push buttons through which you can play and control computer games. Scanner
A scanner is an input device that copies images or printed text and puts them into the computer. Using a scanner, you can directly input the data into the computer without typing it through the keyboard. So, the scanner is also called the direct entry or non-keyboard input device. Web camera
A web camera is an input device that takes photos and puts them into the computer. It is also used to capture videos. It is generally connected to a computer by using a USB (Universal Serial Bus) port. It is widely used in Internet chatting. It is used in messenger programs such as Yahoo! messenger, Windows Live Messenger and Skype. Microphone
A microphone is an input device that is used to input sound into the computer. Using microphone, you can record speech and songs in the computer. It is also used in Internet voice chatting. 42
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Important Points to Remember The input devices are used to give data and instruction to the computer. Keyboard and mouse are the basic input devices. Trackballs are mostly used on laptop computer. By using touch screen, you can use your fingers to select objects and give commands to the computers. Joystick is used to play computer games. Webcam is mostly used in messenger programs such as yahoo messenger, windows live messenger, etc. Microphone is an audio input device.
Exercises 1.
Put a tick ( ) for the correct statements and cross (×) for the false ones.
a.
The most commonly used input devices are mouse and monitor.
b.
You need to press the shift key to type special characters.
c.
Ctrl and Alt keys are used to move the cursor in the document.
d.
To type all the letters in capital, you need to turn off the Alt key.
e.
Right clicking on an item usually displays a list of commands.
f.
The touch screen replaces the use of mouse and light pen. Rising School Level Computer Science, Grade -4
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g. h. i. 2.
Touch pad is mostly used to input pictures into the computer. Microphone in used to input sounds into the computer. Scanner in also called the direct entry input device.
Match the following devices with their uses.
It is widely used in Internet chatting.
It is used to record speech and songs in the computer.
It is used to play games on the computer.
In this screen, we can use our fingers to select objects.
It is used to point objects and give commands to the computer. 44
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3.
Write down the function of the following special keys. Keys
4.
Function
Answer the following questions.
a.
What are input devices? List any four input devices. Ans: .........................................................................................................
b.
.................................................................................................................. What is keyboard? Write different groups of keys. Ans: .........................................................................................................
c.
.................................................................................................................. What is mouse? How can you hold the mouse? Ans: .........................................................................................................
d.
.................................................................................................................. What are different mouse actions? Ans: ......................................................................................................... .................................................................................................................. Rising School Level Computer Science, Grade -4
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e.
What is web camera ? Ans: .........................................................................................................
f.
.................................................................................................................. What is scanner ? Ans: .........................................................................................................
g.
.................................................................................................................. Why do we use joystick in computer ? Ans: .........................................................................................................
h.
.................................................................................................................. What is microphone? Why is it used in computer ? Ans: ......................................................................................................... ..................................................................................................................
5.
Write short notes on:
i. 6.
Touch pad
ii. Touch screen
iii. Scanner
Write single word for the following.
a. b. c. d.
The device which is used to input sound to the computer. Microphone ............................................... Spacebar key The longest key of the keyboard. ............................................... An input device which is used to take photos and put into the computer. ............................................... Web camera The process of pressing left mouse button and moving it together. dragging ...............................................
e.
The device that is used to input graphs, photos and printed Scanner text into computer ................................................
f.
An input device used to play games in computer. Joysticks ...............................................
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7.
Match the following:
Group A a. Mouse b. Joysticks c. Scanner d. Microphone e. Touch pad
Group B Gaming device b Palm sized pointing device a Audio input device d Used in laptop computer e Used in mobile phone and laptop computer f Used to input graph, picture and printed text into computer c
f. Touch screen
8.
Write the names of the following devices:
Keyboard
mouse
scanner
Microphone
joysticks
Web camera
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8.
Complete the given crossword.
M
M J
U
C T P
C L
S
R
E N
I
H
E K
K
R
E
1. 2. 3.
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LAB ACTIVITIES Go to the computer lab then observe the different input devices available there. Ask your teacher to show the working of all available input devices. Try to use some common input devices with the help of your teacher.
Rising School Level Computer Science, Grade -4
Class : 4 Time: 40 Min. 1.
2.
3.
4.
Unit Test Computer science
F.M.: 20 P.M.: 8
Answer the following questions:
6×1= 6
a.
What is computer hardware?
b.
What is input device? Write any two examples of it.
c.
What is touch screen?
d.
What is the use of micro phone?
e.
What is touchpad?
f.
What is dragging?
Match the following:
0.5×4= 2
a.
Microphone
b.
Delete key
c.
Joysticks
(c) Gamming input device (d) Pressing and realizing the mouse buttons (a) Audio input device
d.
Clicking
( b) Delete selected items
Write the technical terms for the following: 0.5×4 =2
a.
Touch sensitive screen. Touch screen
b.
The camera that is used in internet chatting. Web camera
c.
The device that is used to input graphic and printed text directly into the computer. scanner
d.
The device that is used in internet voice chatting. Microphone
State true or false:
a. b.
0.5×4 =2
Battery gives the backup power to the laptop. True To move the pointer on the screen we should move our finger on the keyboard of laptop. False Rising School Level Computer Science, Grade -4
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c. d. 5.
Fill the gaps with appropriate word(s):
Act of pressing he left mouse button twice quickly and realizing it is called_______.Double Clicking
b.
The key that is used to move the cursor to the next line is________. Enter Key Pressing _______ Shift key makes typed letter in capital letter. input devices. Computer takes instruction through _________
d.
7.
50
0.5×4 =2
a.
c. 6.
Pressing and releasing the button of mouse is called clicking. True The function of mouse and touch pad is different. False
Choose the best answer:
0.5×4 =2
a.
Device that is used to point an object on the screen is______. i. Keyboard ii. Canner iii. Monitor iv. Mouse
b.
Touch sensitive pad that is used as pointing device is _______. i. Touchpad ii. Canner iii. Touch screen iv. Mouse
c.
We commonly find touch screen in _______. i. Mobile phone ii. Canner iii. Laptop computer iv. Both (i) and (ii)
d.
To type all letters in capital we should press_________. i. Delete key ii. Space key iii. Back space key iv. Caps lock key
Write short notes on:
a.
Scanner
b.
Joystick
Rising School Level Computer Science, Grade -4
2×2 =4
Chapter
4
PROCESSING DEVICES Before You Read -
Have you seen motherboard? Do you know which device functions as the brain of computer? Have you seen CPU? Have you seen RAM and CPU attached to the mother board?
Computer converts the input data into meaningful information which is called processing. The processing is the main job of the computer. The processing is done in the Central Processing Unit (CPU). CPU is the main processing unit of the computer.
Motherboard
CPU
What is Central Processing Unit (CPU)? The Central Processing Unit is simply called as CPU. It is the main component of the computer and also called the Processor. Computer performs all kinds of processing in the CPU. It executes the program Rising School Level Computer Science, Grade -4
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instructions and tells other parts of the computer what to do. It is considered as the brain of the computer or the computers engine. The CPU is attached directly to a CPU socket on the motherboard. The motherboard is a large circuit board that connects every parts of computer. The motherboard is located inside the system unit (casing box.) The processing speed of CPU is measured in Mega Hertz (MHZ) or Gigahertz (GHZ). It is also called the speed of microprocessor. The working capacity and speed of the computer depend on the CPU. The CPU determines how fast a computer can execute instructions. Now-a-days different types of CPU such as: Intel Celeron, Intel Core 2 Duo, Intel Dual Core, Intel Core i3, Core i5, Core i7, Core i9, etc. are available in the market.
What is the Function of CPU? The main functions of the CPU are as follows: 1. It manages all the resources of the computer. 2. It executes program instructions. 3. It makes decisions. 4. It performs calculations.
What are the Components of a CPU? The CPU has three main components. They are: 1. The Control Unit (CU) 2. The Arithmetic Logic Unit (ALU) 3. Main Memory or Memory Unit (MU) 52
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The structure of CPU is shown in the following diagram.
These units are made on the basis of their work. Each unit has its some specific functions. a.
Control Unit (CU)
Control unit is the most important section of the CPU. It controls and coordinates the activities of the other parts of CPU as well as all the other units of the computer. It controls the entire processing of data inside the computer. It receives the data and instructions from the input device and stores them in the main memory. b.
Arithmetic Logic Unit (ALU)
ALU is another important section of the CPU. It performs all the arithmetic calculations and logical operations on the data. In arithmetic calculations, ALU performs the addition, subtraction, multiplication and division. In logical operations, the ALU compares the numerical data as well as alphabetic data. Rising School Level Computer Science, Grade -4
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A logical unit can usually recognize six logical relationships: equal to, less than, greater than, less than or equal to, greater than or equal to and not equal to. For example, it checks whether the first number is greater than the second, less than the second or equal to second etc. c.
Main Memory
The main memory is also called the primary memory or internal memory of the computer. This memory is used to store program (instructions) and data during the processing. CPU can quickly read/write data and program from the primary memory. Primary memory is fixed on the motherboard inside the computer case. The primary memory are of two types. They are: (i) Read Only Memory (ROM) (ii) Random Access Memory (RAM) Read Only Memory (ROM)
Read Only Memory (ROM) is fixed on the motherboard inside the computer case. It is permanent or non-volatile memory. Its data are not lost even if the computer is switched off. It is read only memory so that you can read data from the ROM but cannot write data into it. ROM stores the instructions for starting up (booting process) the computer. These instructions are stored at the time of manufacture of the computer.
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Random Access Memory (RAM)
Random Access Memory (RAM) is fixed on the motherboard in the memory card slot. It is temporary or volatile memory. The data stored in RAM gets erased when we switch off the computer. RAM is read and write memory so that you can read data from it and write data into it too. RAM is the computer's working memory because the program and data are stored in RAM during processing.
Important Points to Remember CPU is the main processing unit of the computer. The processing speed of microprocessor is measured in Mega Hertz or Giga Hertz. The CPU has main three units: CU, ALU and MU CU controls the operations of all the parts of computer. ALU performs the arithmetic calculations and logical comparison. The main memory is used to store program and data during the processing. The primary memories are of two types: ROM and RAM.
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Exercises 1.
Match the following devices with their function:
It stores the instructions for starting up the computer.
It stores the program and data during processing.
It performs all the operations on data according to program's instructions.
The CPU is attached on it.
It stores most of the components of computer system. 56
Rising School Level Computer Science, Grade -4
2.
Complete the following diagram that shows the structure of CPU:
3.
Fill in the blanks choosing the correct words from the box below:
ROM
ALU
RAM
CU
main
CPU processing
a.
Computer converts data into meaningful information is called ...............................
b.
The main parts of CPU are CU, main memory and ..
........
.
c.
..
........
controls the activities of the other parts of CPU.
d.
RAM and ROM are ..
..........
memory of the computer.
e.
..
..........
is read write memory.
f.
..
..........
stores instructions that are required during startup process.
g.
..
..........
is considered to be the brain of computer. Rising School Level Computer Science, Grade -4
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4.
Answer the following questions:
a.
What is meant by processing ? Ans: ......................................................................................................... ..................................................................................................................
b.
Write the main processing unit of computer. Ans: ......................................................................................................... ..................................................................................................................
c.
Name the different types of CPU available in the market. Ans: ......................................................................................................... ..................................................................................................................
d.
What are the functions of CPU ? Ans: ......................................................................................................... ..................................................................................................................
e.
What are the main components of CPU ? Ans: .........................................................................................................
f.
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.................................................................................................................. What is the main memory ? Ans: ......................................................................................................... ..................................................................................................................
g.
What is RAM ? Ans: ......................................................................................................... ..................................................................................................................
h.
Why is RAM called volatile memory ? Ans: ......................................................................................................... ..................................................................................................................
Rising School Level Computer Science, Grade -4
5.
i.
What is ROM ? Ans: ......................................................................................................... ..................................................................................................................
j.
Why is it called non-volatile memory ? Ans: ......................................................................................................... ..................................................................................................................
Write full forms of the following:
a. 6.
ALU
b.
CU
c. PC
d. RAM
e. ROM
Read the clues and write who am I?
a.
I am electronic brain of computer.
...........................................
b.
I am the part of CPU, you can perform the calculations. ............................................
c.
I am permanent memory of computer ...........................................
d.
I am non-volatile memory and can store data permanently. ............................................
LAB ACTIVITIES
1. 2. 3.
Go to the computer lab then ask your teacher to show inside the system unit. Observe the CPU chip on the motherboard. Ask the teacher to describe about other hardware parts inside the system unit.
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Unit Test Computer science
Class : 4 Time: 40 Min. 1.
2.
3.
4.
60
F.M.: 20 P.M.: 8
Answer the following questions:
6×1 = 6
a.
What is meant by processing?
b.
Why is CPU called brain of computer?
c.
What is RAM?
d.
Why is ROM called non- volatile memory?
e.
What is meant by main memory?
f.
Why is RAM called the working memory of computer?
Match the following:
0.5×4= 2
a.
CU
()
Volatile memory
b.
ROM
()
Performs mathematical and logical operation
c.
ALU
()
Controls the activities of the other parts of CPU.
d.
RAM
()
Permanent memory
Write the technical terms for the following:
0.5×4=2
a.
The brain of computer.
.......................................
b.
The memory that stores data and instruction needed during startup process. .......................................
c.
The temporary memory of computer.
d.
The main printed circuit board of computer. ...................................
.......................................
State true or false:
a.
CPU is the memory unit of computer.
b.
All the processing activities take place in RAM.
Rising School Level Computer Science, Grade -4
0.5×4=2
5.
6.
7.
c.
Data stored in ROM cannot be modified.
d.
The data on RAM are erased when the electricity is cut off.
Fill the gaps with appropriate word(s):
0.5×4=2
a.
Act of converting data into information by computer is called_______.
b.
The different sections of CPU are CU, main memory and ________.
c.
________is read write memory.
d.
RAM and ROM are the ___________ memory of the computer.
Choose the best answer:
0.5×4=2
a.
The CPU speed is measured in terms of__________ i. MHz ii. GHz iii. BIT iv. Both (i) and (ii)
b.
CPU, RAM and ROM are attached to the _______ i. Hard disk ii. Monitor iii. Motherboard iv. All of the above
c.
The primary memory of computer are_________ i. RAM ii. Monitor iii. Motherboard iv. Both (i) and (ii)
d.
The function of CPU are _________. i. Make decisions ii. Perform calculations iii. Execute program iv. All of the above
Write short notes on:
a.
Main Memory
b.
Read only memory (ROM)
2×2=4
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Chapter
5
OUTPUT DEVICES -
Before You Read Where do you see the text that you to have typed in computer? Have you ever seen the speaker? Can you name the device that gives you printed output? Do you see anything on the screen when the power is cut off?
Computers process input data to produce meaningful information that is result. That meaningful information is called an output. The devices, which display the output for the user are called output devices. The output devices receive information from the computer and translate it into a form that we can understand. The output may be in the form of text, graphics, audio (sound) and video. The devices like monitor, printer, plotters and speakers are used to display output in various formats. The monitor, printer and speaker are the basic output devices.
Monitor
Printer
Some of the commonly used output devices are: 1. Monitor 2. Printer 3. Speaker These output devices are described below: 62
Rising School Level Computer Science, Grade -4
Speaker
Monitor Monitor is a primary output device. It is also called the Visual Display Unit (VDU). A monitor displays the output in the form of text, pictures and video. The output that we see on the monitor screen is known as soft copy output. A monitor looks like a common television screen. A monitor has an on/ off button and different control buttons. These control buttons allow us to adjust the brightness and color contrast on the monitor screen. The monitors are of three main types. They are: (i) CRT Monitor (ii) LCD Monitor (iii)
LED Monitor
It is clearly shown in the following diagram. Monitor
CRT Monitor
LED Monitor
LCD Monitor
Now-a-days CRT monitors are not available in the market. Most of the monitors in the market are LCD and LED based. The LCD (Liquid Cristal Display) monitor consumes very less electric power than CRT (Cathode Ray Tube) monitor. It is very lighter and more portable than the CRT monitor. LCD screen does not affect your eyes. So, LCD monitors are popular than CRT monitors. LED is the latest technology of all types of monitors. It has lots of advantages over LCD monitors. Today LED monitors are being the most popular than other monitors. Rising School Level Computer Science, Grade -4
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Printer Printer is an output device that is used to print the output on the paper. The output on the paper is called hard copy output. Different types of printers are available in the market. Some of the most commonly used printers are dot matrix printer, ink jet printer and laser printer. Today the laser printer is being the most popular than other printers.
Dot Matrix Printer
Inkjet Printer
Laser Printer
Speaker The speaker is an output device. The speakers are used in computers to produce different sounds as an output. With the help of speakers, you can listen music and songs played by computer.
Plotter A plotter is a computer vector graphic printer that gives a hard copy output. Plotters use vector graphics. Usually they are used to print to paper which is very large in size. Plotters print things by using special, colored pens. They are also more expensive than ordinary printers. 64
Rising School Level Computer Science, Grade -4
Important Points to Remember The devices, which are used to give the output of the computer, are called output devices. The output devices receive information from the computer and translate it into a form that we can understand. The monitor, printer, and speaker are the basic output devices. The output may be in the form of text, graphics, audio and video. The output displayed by the monitor is called soft copy output. Monitors are of three main types: CRT, LCD and LED Monitor. Nowadays LCD monitors are widely used than CRT monitors. The printed output on the sheet of paper is called the hard copy output. Speakers produce the sound output.
Exercises 1.
Give the name of the devices.
a.
The device that gives the soft copy output ................................
b.
The device that gives hard copy output
c.
The device that gives output in the form of sound .............................
d.
The device that is the most popular printer today ............................
................................
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2.
3.
Put a tick (
) in the correct answer.
a.
Which of the following devices gives soft copy output? ii. Printer i. Monitor
b.
Which of the following gives hard copy output? i. Speaker ii. Printer
c.
Which of the following is an output device? ii. Monitor i. Touch pad
d.
Which of the following printers is the most popular one ? i. Inkjet printer ii. Laser printer
e.
Which of the following is the most popular monitor today? i. CRT monitor ii. LED monitor
Answer the following questions.
a.
What is output of the computer? Ans: ......................................................................................................... ...................................................................................................................
b.
What are the output devices? Write two examples. Ans: ......................................................................................................... ...................................................................................................................
c.
Write each example of hard copy and soft copy output devices. Ans: ......................................................................................................... ...................................................................................................................
d.
What is a monitor? Write its types. Ans: ......................................................................................................... ...................................................................................................................
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e.
What is a printer? Write two examples. Ans: ......................................................................................................... ...................................................................................................................
f.
Write any two differences between CRT and LCD monitor. Ans: ......................................................................................................... ...................................................................................................................
4.
Write full forms of the following.
a. 5.
VDU
b. CRT
c.
LCD
d. LED
Match the following.
Group A Printer Monitor Speaker Plotter
Group B Soft output Dot matrix Output device Audio sound
LAB ACTIVITIES
1. Go to the computer lab then observe the different output devices available there. 2. Ask your teacher to show the working of all available output devices. 3. Try to use some common output devices with the help of your teacher.
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Chapter
6
THE CORRECT WAY OF OPERATING A COMPUTER Before You Read
-
How do you start your mobile phone? Have you ever used computer? Do you have computer at your home? How do you sit while using computer? How do you hold your mouse before you use it? Can you properly shut down your computer?
Computer is an electronic machine that performs tasks according to the instructions given to it. To make a computer work automatically, sets of instructions called program are fed into the computer. The sets of program are called software. Different hardware components and software together form a workable computer system. There must be operating system software to operate a computer systematically. Windows is the popular operating system software. When you turn on the computer then your operating system starts its processing to make the computer ready for you to work. You should work on the computer properly. The improper use of computer can cause harm to your health. So, you should develop the habit of working on the computer in the correct way.
Correct way of Starting and Shutting Down your computer You should know the correct way of starting and shutting down the computer. If you do not do it correctly, it may damage your computer parts. Let us learn how to turn on and off the computer with Windows7 operating system. 68
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Starting your Computer
Step 1: Switch on the main power supply button. Step 2: Switch on the power button on the UPS or Volt guard. Step 3: Switch on the power button of the system unit. It is normally located in the front panel of the casing. 1 Step 4: Switch on the power button of the monitor. 3
After turning on the power button, you have 4 to wait some time. At that time, operating system 2 performs some processing called booting. Then, a username and password may be requested that depends on the configuration of the computer. Otherwise, the operating system will be loaded directly to display the windows desktop. Step 5: If a user name and password is requested, type the user name and password then press the enter key. Then, windows desktop will be displayed on the monitor screen. Now your computer is ready for you to work.
Shutting Down Your Computer You should turn off the computer properly. Never turn off the computer directly pressing the power button. It may harm the different parts of your computer. First shutdown the windows and then turn off the computer. Rising School Level Computer Science, Grade -4
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Step 1: First of all, save your work and close all the programs that you have opened. Step 2: Click on the Start button and click on the droup down button situated at the bottom right of dialogue box. Then, it displays a list of options like: Switch user, Log off, Lock, Restart, Shut down etc. Step 3: Click on the Shut down option. Then your computer will shut down. Step 4: Turn off the power button of monitor. Step 5: Turn off the main power supply button.
Correct Way of Arranging Computer Parts Computer Parts should be placed in the right place. The keyboard, mouse and monitor should be placed in the proper place. If the computer parts are not put in the right place that may cause different health problems. Some tips to arrange the computer parts correctly are given below: 1. The position of the monitor, keyboard and mouse should be adjusted according to your comfort. 2. The keyboard and mouse must be placed in front of the monitor. This prevents the frequent movement of your head. 70
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3.
The keyboard and mouse should be closely placed to each other and at the same height. 4. There should be enough space to use mouse. 5. Your chair should be of right height for you.
Correct Way of Using Computer Mouse You should hold and use the mouse correctly. Holding and moving a mouse incorrectly can cause injury to your wrists, hands, and arms. Here are some tips for using mouse safely. 1. Always use the mouse by placing it on the mouse pad. 2. Place your mouse at elbow level. Your upper arms should fall relaxed at your sides. 3. Hold the mouse gently. Do not grip it tightly. 4. Avoid bending your wrist up, down, or to the sides. 5. Use a light touch when clicking a mouse button. 6. Keep your fingers relaxed.
Wrong!
Right!
Wrong!
Right! Rising School Level Computer Science, Grade -4
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Correct Way of Using Computer Keyboard You should use the keyboard correctly while typing on it. Using the keyboard improperly can cause injury to your wrists, hands and arms, particularly if you use computer for long periods of time. Here are some tips for using keyboard safely. 1.
Place your keyboard at elbow level. Your upper arms should be relaxed at your sides.
2.
Center your keyboard in front of you.
3.
Type with your hands and wrists floating above the keyboard, so that you can use your whole arm to reach for distant keys instead of stretching your fingers.
4.
Avoid resting your palms or wrists on any type of surface while typing.
5.
While typing, use a light touch and keep your wrists straight.
6.
Do not press the keys on the keyboard too hardly. Wrong!
Right! Wrong!
Right! 72
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Safety Habits While Working on the Computer While working on the computer, you should have right posture. If your posture is wrong, you may feel pain in your wrist, fingers, back, neck , etc. Due to wrong posture, you may suffer from eye diseases like computer vision syndrome (CVS). So you must follow some safety habits while working on the computer continuously for long period of time. Some safety habits are given below: 1.
Your eyes should not be too close to the monitor. There should be at least 20 inches distance between your face and the monitor.
2.
The monitor should be positioned slightly below the eye level.
3.
Rest your eyes by looking away from the screen frequently.
4.
Your back should be absolutely straight and should touch the backrest of the chair. 20'-28' To Screen
Sitting Eye Height 10'-20' Monitor Tilt
Sitting Elbow Height Seat Height
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5. 6. 7. 8.
Your feet should be flat on the floor. Your arms should be placed parallel to the floor and the elbow should be placed a little higher than the height of the keyboard. While typing on the keyboard, keep your wrist straight and parallel to the floor. Take break of 1-2 minutes after every 30 minutes of continuous work.
Important Points to Remember While working on the computer, you should have right posture. We should not turn off the computer directly pressing the power button. The wrong use of computer causes harm to your health. There should be right arrangement of computer parts. The keyboard and mouse should be closely placed to each other and at the same height. Hold the mouse gently. Do not grip it tightly. Do not press the keys on the keyboard too hardly.
Exercises 1.
74
Write 'T' for true statements and 'F' for false ones.
a.
Sets of programs are called software.
T
b.
Programs are the sets of instructions.
T
c.
Only hardware can make complete computer system.
F
Rising School Level Computer Science, Grade -4
d.
While working on the computer, you should have right posture.
T
e.
We should turn off the computer directly pressing the power button.
F
f.
The wrong use of computer causes harm to your health.
T
g.
We should hold the mouse tightly.
F
h.
We should press the keys on the keyboard too hardly.
F
2.
Put a tick ( ) for correct ways and cross (×) for wrong ways in the following pictures.
3.
Fill in the blanks.
a. b.
software together form Different hardware components and ...................... a workable computer system. power button Never turn off the computer directly pressing the .......................... Rising School Level Computer Science, Grade -4
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c. d. 4.
below The monitor should be positioned slightly ..................................... the eye level. too hardly Do not press the keys on the keyboard ..................................
Answer the following questions.
a.
Write down the steps to start your computer. Ans: ......................................................................................................... ...................................................................................................................
b.
Write down the steps to shut down your computer. Ans: ......................................................................................................... ...................................................................................................................
c.
Explain the correct ways of using mouse. Ans: ......................................................................................................... ...................................................................................................................
d.
Explain the correct ways of using keyboard. Ans: ......................................................................................................... ...................................................................................................................
e.
Write down any four safety habits while working on the computer. Ans: ......................................................................................................... ...................................................................................................................
f.
What is computer software? Ans: ......................................................................................................... ...................................................................................................................
g.
What is computer system? Ans: .........................................................................................................
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h.
What happens when you start your computer ? Ans: ......................................................................................................... ...................................................................................................................
LAB ACTIVITIES
1.
Go to the computer lab then practise the correct ways of using mouse and keyboard.
2.
Arrange the computer parts correctly.
3.
Learn about safety habits while working on the computer.
4.
Draw the figure of the correct way of using the computer and patch on the wall of computer lab making different groups.
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Class : 4 Time: 40 Min. 1.
2.
3.
4.
78
Unit Test Computer science
F.M.: 20 P.M.: 8
Answer the following questions:
7×1=7
a.
What is meant by output device? List two examples.
b.
What is printer? Write its types.
c.
What is speaker?
d.
What is monitor?
e.
Write any one difference between CRT and LCD Monitor.
f.
What is softcopy output?
Match the Following:
0.5×4=2
a.
Hard copy output
( ) Consumes very less electric power and is light in weight.
b.
Monitor
( ) Output printed on paper
c.
LED
( ) Audio output device
d.
Speaker
( ) Also called VDU
Write the technical terms for the following:
a.
The device that gives softcopy output device.
b.
The device that gives output in the form of sound.
c.
The monitor that is similar to our common TV.
d.
The device that gives output on the paper.
State true or false:
a.
CRT monitor is lighter than LCD.
b.
Plotter is an example of output device.
Rising School Level Computer Science, Grade -4
0.5×4=2
0.5×4=2
5.
c.
Monitor is used to listen music.
d.
The output may be in the form of text, graphic, sound etc.
Write the full form:
a. 6.
7.
VDU
b. CRT
0.5×4=2
c. LCD
d. LED
Choose the best answer:
0.5×4=2
a.
Which of the following devices gives softcopy output? i. Monitor ii. CPU iii. Mouse iv. Both (i) and (ii)
b.
Which of the following gives hard copy output________ i. Monitor ii. CPU iii. Both (i) and (iv) iv. Printer
c.
Which of the following is output device? i. Monitor ii. CPU iii. Both (i) and (iv) iv. Printer
d.
The most popular printer is___________ i. CRT ii. LCD iii. LED iv. Both (ii) and (iii)
Write short notes on:
a.
Monitor
b.
Speaker
2×2=4
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Chapter
CONCEPT OF OPERATING SYSTEM
7 -
Before You Read What happens when you start a computer? What do you see on the screen after your computer is started? Can you name the items that you see on the screen? The picture that you see on the screen are called icons.
Introduction to Operating System Every computer must have an operating system to run other programs and applications. Operating systems perform basic tasks. An operating system is a special software that manages and controls all the parts of a computer system. A manager manages and controls all the activities on an organization, in the similar way an operating system controls and manages all the activities of the computer system. So, an operating system can be considered as the manager of the computer. It manages the functions of all the hardware and other software used in the computer. Examples of some operating system software are Windows, DOS, LINUX and UNIX.
OS 80
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What is Microsoft Windows? Microsoft windows is the most widely used operating system software. It was developed by an American software company Microsoft Corporation. It is a Graphical User Interface (GUI). In Windows, you can perform different tasks by clicking on the icons by using the mouse instead of typing commands. So, it is easy to use. Windows operating system is available in different versions such as Windows- 95, Windows- 98, Windows- 2000,Windows- XP, WindowsVista, Windows- 7, Windows 8, Windows 8.1, Windows 10, etc. Among them, Windows-10 is the most popular version of windows operating system. After Windows-8.1, Microsoft released next versions of windows as Windows 10. Windows-10 provides many more facilities than the earlier versions of windows. The windows operating system and their released dates are listed below. OS name
Released date
1.
Windows - 95
August - 1995
2.
Windows - 98
June - 1998
3.
Windows - 2000
February - 2000
4.
Windows - XP
October - 2001
5.
Windows - Vista
January - 2007
6.
Windows -7
October - 2009
7.
Windows - 8
October - 2012
8.
Windows - 8.1
August - 2013
9.
Windows - 10
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Starting Your Computer with Windows You can easily start and operate your computer with windows operating system because it provides a graphical user interface. Just you have to switch on your computer, then Windows starts up your computer automatically. To start the computer, follow these steps: Step 1: Switch on the power supply button. Step 2: Switch on the UPS/ volt guard. Step 3: Switch on the power button of the System Unit (Casing). Step 4: Switch on the power button of monitor. Then windows performs some internal processing to start your computer. This is called booting. After completing booting process, your computer may ask you to enter the user name and password. Step 5: Type the user name and the password if asked. Then press the Enter key. Then windows desktop appears on your monitor screen.
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What is Booting? The process of starting a computer is called Booting. During the Booting process, your computer transfers system files (program files) from any storage devices such as hard disk to the main memory of the computer (RAM). It also checks the various components of computer to make it ready to work.
Windows-10 Desktop After starting the computer, the windows desktop appears on your monitor screen as shown below. You can see different elements in the windows desktop. The Icons, the Start button, the Task bar and the Desktop are the main elements of Windows desktop.
Icons
Start Button
Quick lunch
Taskbar
System date and time
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Icons on Windows Desktop In the desktop, you can see several small picture buttons with their name. These small picture buttons represent commands, programs, files or folders stored in your computer. These are called icons. You can run programs, open files or folders and give commands by double-clicking on these icons. Normally, the following icons appear on the window-XP desktop.
This PC
This icon represents a folder that provides access to the resources on your computer. You can access disk drives and other peripherals by double-clicking on the Computer icon. When you open the This PC icon, it shows the components available in your computer. It shows the icons for hard disk drive, CD/DVD drive, printer and any other devices attached to your computer. My Documents
This icon represents a folder where the computer automatically stores your saved documents. It provides the access to store or open your document. You can access your saved documents by double-clicking on this icon. 84
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Recycle Bin
This icon represents a folder that stores all the deleted items from the computer. When you delete any item from the computer, windows sends them to the recycle bin. It can be considered as the dustbin of the computer. It also allows you to recover them later or delete permanently. You can access your deleted items by double-clicking on this icon. Internet Explorer This icon represents a program that allows you to use Internet. You can launch internet explorer browser by double-clicking on this icon. Network
This icon provides access to use the shared resources of the other connected computers in the network. Arranging the Icons on the Desktop You can place the icons on the desktop according to your requirement. You can arrange icons by dragging or sorting. Step 1: Right Click on any blank area of the desktop. Then appears a list of menu. Step 2: Move the mouse pointer to "Sort By" option. Then appears a submenu. Rising School Level Computer Science, Grade -4
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Step 3: Click on the Name or Size or Item Type or Date modified. Then the icons on the desktop will be re-arranged according to your selection. Changing Background of your Desktop
You can change the background of the Windows desktop to make your favourite look. Step 1: Right Click on any blank area of the desktop. Then appears a list of menu. Step 2: Click on "Personalize". Then appears Personalization window. Step 3: Click on the Background option. Step 4: Select your favourite background picture from the list. If you want to add pictures from your computer as desktop background, click on browse option. Locate the picture and click on Choose picture option. Then your desktop changes with new background. 86
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Setting Up the Screen Saver
A screen saver is a moving pattern or picture that appears on the screen when you leave your computer on for some time without working on it. Generally, the screen saver is used for entertainment. You can set up your own screen saver. Step 1: Right Click on any blank area of the desktop and select personalize. Step 2: Click on "Personalize". Then appears Personalization window.
Step 3: Click on the Lock Screen option from the left side of the window. Step 4: Click on the Screen Saver Setting option from the Lock Screen window. Then Appears Screen Saver Setting dialog box. Step 4: Select your favourite screen saver from the Screen saver menu. You can also set the required time for wait. Rising School Level Computer Science, Grade -4
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You can see its preview by clicking on the Preview tab. Step 5: Click on the Apply button and click on OK button. Now your screen saver is changed.
The Start Button You can see a windows button located at the left corner of the taskbar. This button is called start button. When you click on the start button, it displays different menus. You can open several programs from All Programs menu. Tips: Press windows logo key ( ) to display the start menu items.
Opening a Program by using Start Menu
When you click on the Start button, then appears a list of menu items. These menu items are called start menu items. You can see an arrow with some menu items. If you click on that arrow, another menu appears on your screen. That is called submenu. To open the Start Menu item, follow these steps: Step 1: Click on the start button. Than appears a list of programs and program folder installed on your computer. Step 2: Click on the item that you want to open. 88
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Opening the Calculator Program
The Windows has a calculator program. You can solve different mathematical problems by using this program. This program works exactly like your hand-held calculator. Step 1: Click on the Start button. Step 2: Then select the All Programs option. Step 3: Then select the Accessories option. Step 4: Click on the Calculator. Then the Calculator program's window appears. Now you can do your calculations by using this calculator. To perform calculations, press the different buttons on the calculator by using mouse. You can also type numbers from the keyboard.
Shutting Down Your Computer After completing your work on the computer, you need to shut down your computer. Never turn off the computer pressing the power button directly. It may harm the internal parts of your computer. You have to shut down windows before you turn off your computer. Before shutting down windows, save all your work and close all the opened programs. To shut down the computer, follow these steps: Step 1: Click on the Start button. Then start menu will display. Rising School Level Computer Science, Grade -4
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Step 2: Click on the power option situated at the bottom left corner of start menu. Step 3: From the displayed list click on the Shut down option. After some time your computer will be turned off. Then you need to turn off the power button of the monitor.
Important Points to Remember Windows in the most popular operating system software. An operating system software manages and controls all the parts of the computer system. Windows is available in different versions such as WindowsXP, Windows -Vista, Windows -7, Windows - 8, Windows - 10 etc. The process of starting your computer is called booting. Small picture buttons that present commands, programs or files are called icons. A screen saver is a moving pattern or picture that appears on the screen when you leave your computer on for some time without working on it. Calculator is a program that is used to perform calculations. Recycle bin stores deleted items. My document is the folder where saved documents are automatically stored. 'This PC' is the folder that provides access to the resources of the computer. 90
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Exercises 1.
Label the following Windows10 screen.
Icons
Quick lunch
Start button
2.
System date & time
Taskbar
Write down the name of the following icons and also write down their functions.
Icon
Icon name This PC My Document
Recycle bin Internet explorer
Network
Functions It provides access to the resources of the computer It is a folder that allows us to save document automatically in computer.
It saves all the deleted items of the computer It allows us to surf Internet It provide access to use shared resources of other connected computers in the network. Rising School Level Computer Science, Grade -4
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3.
4.
Fill suitable words in the blanks choosing right word from the box. Recycle bin Icons Mouse GUI OS
a.
GUI Microsoft Windows is an .................................software.
b.
OS .......................... manages the function of all the hardware and other software used in the computer.
c.
Icons ......................... are small picture buttons that represent commands, programs, files or folders stored in your computer.
d.
When you delete any item from the computer, windows sends Recycle bin them to the ......................
e.
Mouse ......................... is used to select and move items on the computer screen and to give different commands to the computer.
Write 'T' for true statements and 'F' for false ones.
a. b. c. d. e. f. g. h. i. 92
Windows in the most popular operating system software. The process of starting your computer is called shutting down. Small picture button that presents commands, programs or files is called My computer. A screen saver is a moving pattern or picture that appears on the screen. Microsoft windows is CUI based OS ? When we switch on the computer Ms. Windows is loaded at first. The area that appears on the screen when we start the computer is desktop area. My document is the folder where saved documents are automatically stored. Recycle bin stores deleted items.
Rising School Level Computer Science, Grade -4
True False
False
True False
True True
True True
5.
Answer the following questions.
a.
What is an operating system? Ans: ......................................................................................................... ...................................................................................................................
b.
Write any four examples of operating system. Ans: ......................................................................................................... ...................................................................................................................
c.
What are different versions of windows? Ans: ......................................................................................................... ...................................................................................................................
d.
What is booting? Ans: ......................................................................................................... ...................................................................................................................
e.
What are the different parts of Windows -7 desktop? Ans: ......................................................................................................... ...................................................................................................................
f.
What is desktop area? Ans: ......................................................................................................... ...................................................................................................................
g.
Write any four default icons of Desktop. Ans: ......................................................................................................... ...................................................................................................................
h.
What is Recycle Bin? Ans: ......................................................................................................... ................................................................................................................... Rising School Level Computer Science, Grade -4
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i.
What is Internet Explorer? Ans: ......................................................................................................... ...................................................................................................................
j.
What is an Icon? Ans: ......................................................................................................... ...................................................................................................................
k.
What is Screen Saver? Ans: ......................................................................................................... ...................................................................................................................
6.
Chooses the best answer.
a.
b.
c.
d.
94
Which of the following is GUI base operating system? i. Ms. DOS
ii. Ms. Windows-7
iii. Ms-Windows 10
iv. Both (ii) and (iii)
The Icon that is used to access the resources of the computer is________. i. Recycle bin
ii. My document.
iii. This PC
iv. Internet explorer
The gateway to computer program is _________ i. Reset button
ii. Power button
iii. Start button
iv. None of the above
The program that allows us to use internet is __________ i. Internet explorer
ii. Word pad
iii. Calculator
iv. All of the above
Rising School Level Computer Science, Grade -4
7.
e.
My document folder stores___________ i. Deleted document ii. Seen document iii. Un seen document iv. Saved document
f.
Small picture representing file folder, program etc. is ____________ i. Icon ii. Button iii. Screen saver iv. None of the above
Write the steps to perform the following tasks.
a.
To start the computer
b.
To change background of your desktop
c.
To set up the screen saver
d.
To open the calculator program
e.
To shut down computer LAB ACTIVITIES
1.
Start the computer.
2.
Change the background of your computer.
3.
Set up your favourite screen saver.
4.
Open the calculator program then perform the following calculations. i.
25 + 28 - 20 ÷3 × 5 =
iii. 97 - 30 + 45 ÷ 2 × 55 = 5.
ii.
69 + 10 - 20 =
iv. 200 × 50 - 500 + 500 =
Shut down the computer.
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Class : 4 Time: 40 Min. 1.
2.
3.
4.
96
Unit Test Computer science
F.M.: 20 P.M.: 8
Answer the following questions:
a.
What is an Operating System? Write with example.
b.
What is desktop area?
c.
What is Recycle Bin?
d.
What is the use of 'My Computer' icon?
e.
What is booting?
f.
List any four default icons of desktop.
Match the following:
6×1=6
0.5×4=2
a.
Windows- 8
( ) Gateway of any program
b.
Internet Explorer
( ) GUI based operating system
c.
Screen saver
( ) Program that allows to use internet
d.
Start button
( ) Moving pattern or picture
Write 'T' for true statements and 'F' for false ones.
0.5×4=2
a.
MS- DOS is GUI based operating system.
b.
When we switch on the computer windows is loaded at first.
c.
My Document is the folder where saved documents are stored.
d.
My computer displays the system folder and drives in use.
State true or false:
a.
CRT monitor is lighter than LCD.
b.
Plotter is an example of output device.
Rising School Level Computer Science, Grade -4
0.5×4=2
5.
6.
7.
c.
Monitor is used to listen music.
d.
The output may be in the form of text, graphic, sound etc.
Write down the steps:
2×2=4
a.
To set up the screen saver.
b.
To change the background of your desktop
Choose the best answer:
0.5×4=2
a.
Which of the following is GUI based OS? i. MS- DOS ii. Windows 7 iii. Windows 10 iv. Both (ii) and (iii)
b.
The icon that is used to access the resources of the computer is_________ i. My document ii. My computer iii. Internet Explorer iv. Network
c.
The picture representing file, folder or program is _________ i. ICON ii. Button iii. Power Button iv. Reset Button
d.
The icon that stores deleted items is_________ i. Recycle bin ii. My computer iii. Control panel iv. All of the above
Write short notes on:
a.
OS
b.
Screen saver
1×2=2
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Chapter
8
TYPING WITH TUX TYPING
Tux Typing is a free and open source typing software created especially for children. It features several different types of game play, at a variety of difficulty levels. It is designed to be fun and educational to improve WPM (Words Per Minute) speed of typists. NOTE : The number of words that a user can type in a minute is called WPM speed.
Starting Tux Typing To start Tux Typing software, follow the following steps : Step 1: Click on Start Button in the taskbar. Step 2: Lockate Tux Typing program and click on it. Now, you have started Tux Typing software.
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Tux Typing software contains varieties of typing games according to the interest of children.
Playing a game in Tux Typing Tux Typing includes two types of typing games. They are : 1. Fish Cascade 2. Comet Zap To play a game, follow these steps : Step 1: Start Tux Typing. Step 2: Click on the Game which you want to play. (Fish Cascade or Comet Zap) Step 3: Select the difficulty level (Easy/ Medium/ Hard). Step 4: Choose the area of your interest. Step 5: Start Playing.
2
3
4
Fish Cascade Game
Fish Cascade is a type of game available in Tux Typing software. In this game, fishes with letters go on falling and the user has to type the letters given. Rising School Level Computer Science, Grade -4
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Comet Zap Game
Comet Zap is another type of game available in Tux Typing software. In this game, a user has to type all the letters falling as a comet.
Typing Lessons To increase the typing skills of children, lessons are available in Tux Typing. Numbers of lessons are given on the basis of difficulty. 100
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To start a lesson, follow these steps : Step 1: Click on lesson menu from the main menu. Step 2: Choose the type of lesson you require. Step 3: Press Space key to start. Step 4: Again press P key to continue. Step 5: Now, you can start typing.
Important Points to Remember Tux Typing is a free and open source typing software created especially for children. Tux Typing includes two types of typing games. They are : Fish Cascade and Comet Zap. In Fish Cascade game, fishes with letters go on falling and the user has to type the letters given. Rising School Level Computer Science, Grade -4
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In Comet Zap game, a user has to type all the letters falling as a comet. To increase the typing skills of children, lessons are available in Tux Typing.
Exercises Answer the following :
a.
b.
c.
d.
e.
What is Tux Typing? Write its use. Ans: ......................................................................................................... ................................................................................................................... How can we play a game in Tux Typing? Ans: ......................................................................................................... ................................................................................................................... What are the different types of games available in Tux Typing? Describe each in brief. Ans: ......................................................................................................... ................................................................................................................... What are Lessons in Tux Typing? Ans: ......................................................................................................... ................................................................................................................... Why is Tux Typing called a high quality typing software ? Ans: ......................................................................................................... ................................................................................................................... LAB ACTIVITIES Take your WPM speed upto 38 WPM in basic_lesson_06.xml lesson.
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Chapter
9
WORD PROCESSING PROGRAM: WORDPAD
Before You Read - Have you ever printed any document related to you? - Do you know which program is used to prepare document? - Do you know how should you place your finger on keyboard to type document?
WordPad is a basic word processor program that comes with windows operating system. A word processor is a computer program that you can use to create, edit, view, format and print text documents. It is more advanced than NotePad but simpler than Microsoft Word. With WordPad, you can type letters, book reports, and other simple documents. You can also format the text and copy or move the text in the document. In WordPad, you can format and print the text but it does not have intermediate features such as spell checker, thesaurus and support for tables.
Starting WordPad To start WordPad with windows-10 operating system, follow these steps: Step 1: Click on the Start Menu. Then start menu opens. Step 2: Locate windows Accessories folder and click on it. Step 3: Click on WordPad. Then WordPad program's window appears. Rising School Level Computer Science, Grade -4
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Parts of WordPad window The parts of WordPad window are shown in the following picture. 1
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2/ Quick Access Toolbar 2. Title Bar 3. Ribbon
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4. Ruler 5. Text Area 5
6. Control Buttons 7. Status Bar 8. Zoom Control
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Creating and Saving document Step 1: Open WordPad program. Step 2: Type text on text area. Step 3: Click on File menu. Step 4: Click on Save. [Or perss Ctrl + s key from keyboard] Then displays a SaveAs dialogue box. Step 5: Give file name for your document in File name box. Step 6: Click on Save button. 104
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Closing document Step 1: Click on WordPad menu. Step 2: Click on Exit button. OR Click on close ( ) button on the top left side of the WordPad window.
Opening document To open document double click on saved document.
Typing Text When you start WordPad program, a blank new document is automatically opened. You can see a blinking vertical line in the document area. This flashing vertical line is called cursor. The cursor indicates where the next text that you type will appear. To move the cursor within the text, click where you want the cursor to appear. Rising School Level Computer Science, Grade -4
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Some Rules while typing text in the WordPad:
i.
While typing in WordPad you do not have to press Enter key to start a new line. WordPad automatically starts a new line when you reach the end of line. This feature of WordPad is called word wrap.
ii.
When you want to start new paragraph press Enter key.
iii. Press spacebar to separate words in the same line. iv. For capital letter, hold down the shift key then type. v.
To delete characters from the left side press backspace key.
vi. To delete a character from the right side, press Del key. vii. Use left, right, up or down arrow to move the cursor in the document. Or click mouse button where you want the cursor to appear. 106
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Selecting the Text Whenever you want to do something to the text, you need to select it first. Step 1: Position the mouse pointer from where you want to begin your selection. Step 2: Click and hold the left mouse button and drag the mouse pointer over the text that you want to select.
Step 3: The selected text will be highlighted. Step 4: Once you have completed your selection, release the mouse button. You can select required text in the document by following different methods. 1. To select a word : Double click on particular word. Rising School Level Computer Science, Grade -4
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2. 3.
To select a paragraph : Triple click on any word in particular paragraph. To select all the words in the document: Press [Ctrl + a] button from keyboard.
Copying and Moving Text Suppose, you have text in one part of your document and you want to appear that text in another part. For this purpose, copying or moving methods will be more useful. Copy and paste commands are used to copy the text from one part of your document to another part. Copy command does not remove the selected text from the original location. Cut and paste commands are used to move any text from one part of your document to another part. The Cut command removes the selected text from the original location. To copy a text and paste it in another location, follow these steps: Step 1: Select the text that you want to copy. Step 2: Click on the Copy button from the Home tab of Clipboard group. [Or press Ctrl + C from the keyboard]
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Step 3: Move the cursor to the location where you want to insert the copied text. Step 4: Click on the Paste button from the Home tab of Clipboard group and click on Paste option. [Or press Ctrl + V from the keyboard] To move a text to different location, follow these steps: Step 1: Select the text that you want to copy. Step 2: Click on the Cut button from the Home tab of Clipboard group. [Or press Ctrl + X from the keyboard] Step 3: Move the cursor to the location where you want to move the text.
Step 4: Click on the Paste button from the Home tab of Clipboard group and click on Paste option. [Or press Ctrl + V from the keyboard]
Undo Command If you make a mistake while you are editing the text in your document, you can cancel it by using the undo command. The undo command cancels your last action. Step 1: Click on undo arrow ( ) in quick access toolbar. OR
Press [Ctrl+ Z] keys from the keyboard. Rising School Level Computer Science, Grade -4
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Redo Command After applying undo command if you want to calcel undo task then redo command is used. Step 1: Click on Redo arrow ( ) in quick access toolbar. OR
Press [Ctrl+ Y] keys from the keyboard.
Formatting Document Formatting refers to arrangement of texts in proper manner. WordPad provides different features to format your document. For example, you can choose different font styles, color, font size, alignment, etc. Changing Font, Font Styles, or Font Size
To change font style or color or size of the text follow these steps. Step 1: Select the text whose formatting you want to change. Step 2: Go to the on the Font group of Home tab to change the font type, style colour, etc. Font type Font size
Font colour
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Inserting pictures To insert the pictures in the Document follow these steps: Step 1: Place the cursor where you want to insert the picture. Step 2: Click on the picture option from home tab in Insert group. Then appears a list of options. Step 3: Click on Picture option.
Then, appears a Select Picture dialogue box.
Step 4: Select the required picture from your computer. Step 5: Click on the Open option. Then the selected picture will be placed on your document. Rising School Level Computer Science, Grade -4
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Important Points to Remember
WordPad is a basic word processor program that comes with windows operating system. To format the text, you need to select it first. Copy and paste commands are used to copy the text from one part of your document to another part. Cut and paste commands are used to move any text from one part of your document to another part. The undo command cancels your last action. Formatting refers to arrangement of texts in proper manner. We can change font, font style, font size, etc. from the home tab in front group.
Exercises 1.
Label the different parts of WordPad window: 1
2
Quick access toolbar 1. ........................................................
6
Title bar 2. ........................................................
Ribbon 3. ........................................................ 3
Ruler 4. ........................................................
4
Text area 5. ........................................................
5
7
Control buttons 6. ........................................................ 8
Status bar 7. ........................................................ Zoom control 8. ........................................................
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2.
3.
Fill in the blanks: word processor
a.
WordPad is a basic ..................... program.
b.
selec it first. To format the text, you need to ...................
c.
copy paste commands are used to copy the text ................. and ................. from one part of your document to another part.
d.
paste commands are used to move text from cut ................... and ................ one part of your document to another part.
e.
undo The .................. command cancels your last action.
Write the steps to perform the following tasks:
i.
To start WordPad
ii.
To select a text
iii. To copy and paste the text iv. To change font styles v.
To change font color
vi. To save a document vii. To open an existing document 4.
Answer the following questions:
a.
What is word processor?
b.
What is WordPad?
c.
Write the different parts of WordPad window.
d.
What are the different methods for selecting document?
e.
What is difference between copying and moving text?
f.
What is the use of undo common? Rising School Level Computer Science, Grade -4
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5.
6.
g.
What do you mean by formatting a document?
h.
What is the short cut key to save a document.
Match the following:
Group B
a. Microsoft word
cancels previous action
b. Ctrl + S
saves the document
c. Ctrl + C
selects all text, graphic etc.
d. Ctrl + A
word processing software repeats the last action
e. Ctrl + V
saves document
f. Ctrl + Z
to paste text, graphic etc.
g. Ctrl + X
to copy selected text
h. Ctrl + Y
to cut selected text
State true or false:
a.
Word pad is a spread sheet program.
b.
We should press Enter key to start new line in WordPad. True Title bar displays the document name. True
c.
False
d.
To delete character from the right side we should press False 'Tab key'.
e.
Cut and paste command moves the text to new location. True 'Redo' command repeats the last action performed on True the document.
f.
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Group A
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7.
g.
We should press arrow keys to move the cursor in different place of the document. True
h.
We should hold the shift key and press letter to type it in capital letters. True
Choose the best answer:
a.
Which of the following is word processing software? i. Ms-Word ii. WordPad iii. Ms-Excel iv. Both (i) and (ii)
b.
The combination of the key that we should press to copy the text is___________ i. Ctrl + X ii. Ctrl + Z iii. Ctrl + C iv. Ctrl + Y
c.
Formatting refers to ____________ i. Typing text ii. Editing text iii. Arrange text in proper manner iv. None of the above
d.
The command that is used to move the selected text is_________. i. copy/ paste ii. cut/ paste iii. paste/ cut iv. copy/ cut
e.
Whenever we want to do something on the text we need to ___________. i. Select it first ii. See it first iii. Think first iv. None of the above.
f.
The command that cancels the last action is__________. i. Redo ii. Undo iii. Copy iv. All of the above Rising School Level Computer Science, Grade -4
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LAB ACTIVITIES 2/
Type the following document in WordPad and format it as given below:
Today computers are becoming an import part of everyday life. Computer is such a powerful machine that can perform several tasks. So it is used in all most all the fields such as, education communication business, Industry, Entertainment, arts, etc. It is making our works more easier and faster. A computer can perform simple tasks such as typing letter, to more complex task such as lunching rocket.
2.
Save this document as a file name doc1, on the desktop.
3.
Close the WordPad program.
4.
Now, double click on the doc1 file from the desktop to open it. And then add this paragraph on this document.
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Class : 4 Time: 40 Min. 1.
2.
3.
4.
Unit Test Computer science
F.M.: 20 P.M.: 8
Answer the following questions:
6×1=6
a.
What is word processor?
b.
What is document formatting?
c.
What is Redo command?
d.
What is the difference between copy past/cut pastes?
e.
What is undo command?
f.
What should be done to select particular word in WordPad?
Match the following:
0.5×4=2
a.
Ctrl + S
( ) copies the selected text
b.
Ctrl + C
( ) saves the document
c.
Ctrl + Z
( ) repeats the last action
d.
Ctrl + Y
( ) cancels the last action
Fill in the blanks:
0.5×4=2
a.
Work pad is a basic ______________ program.
b.
To format the text you need to __________it first.
c.
_______ and __________ command is used to copy the text to new location.
d.
We should press __________key to begin new line.
State true or false:
0.5×4=2
a.
Word pad is an operating system.
b.
Title bar of the WordPad displays the document name. Rising School Level Computer Science, Grade -4
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5.
6.
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c.
We should press enter key to move the cursor in different place of the document.
d.
We should not save the document when we complete it.
Write down the steps:
a.
To save a document
b.
To insert picture in the document
c.
To change the font color
Choose the best answer:
3×2 = 6
0.5×4 = 2
a.
Which of the following is word processing software? i. MS-DOS ii. Windows 7 iii. Windows 10 iv. WordPad
b.
The combination of the keys that should be pressed to copy the text is________ i. Ctrl + X ii. Ctrl + Y iii. Ctrl + C iv. Ctrl +V
c.
The command that is used to move the selected text is ________ i. copy/ paste ii. paste/ copy iii. paste/ cut iv. cut/ paste
d.
Whenever we want to do something on the text we need to _________ i. select it first ii. read it first iii. see it first iv. none of the above
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Chapter
10
WORKING STEP-BY-STEP
In your real life, you are doing every work step-by-step. There will be pre-defined steps to complete any work. You must go through these steps to complete that work. You must follow the steps in correct order, one -by -one. You should not skip any steps. If you skip one or more steps, the work will not be completed well. Let us take some examples
To watch Television 1.
Complete you homework.
2.
3.
Switch on the TV.
Watch the TV.
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4.
Switch off the TV.
What will happen if you try to perform this task in the following order. 1. Switch off the TV. 2. Watch the TV. 3. Switch on the TV. 4. Do homework. Is watching TV after switching off possible? Surely, not possible. So, you must do work in correct order one- by -one. To Eat an Orange
1.
Wash your hands.
2.
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Peel the orange.
3.
Eat the orange.
4.
Throw the peel and seeds in the dustbin.
To get ready for school
1.
Clean your body.
2.
Put your books in your school bag.
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3.
Have your breakfast.
4.
5.
Put on school uniform.
Go to school.
In the same way a computer also does any work step-by-step. Computer needs step-by-step instructions to do any work. But the computer cannot define steps itself. The step-by-step instructions for the computer are defined by the programmer. This is called computer programmer. A computer performs works by following the steps defined in the program. To get the proper result in the computer, the instructions should be given in right order. Computer also needs clear instructions to do any work. If you give vague instructions, your computer will not know what to do. 122
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Important Points to Remember There will be pre- defined steps to complete any work. You must go through these steps to complete that work. You must follow the steps in correct order one-by -one. Computer also does any work step-by-step. A computer performs works by following the steps defined in the program. A computer needs clear instructions to do any work.
Exercises 1.
Arrange the following steps in correct order by numbering them: a.
To eat an orange 4 1st step ................. 1
2nd step ................. 3 3rd step ................. 2 4th step .................
1
2
3
4
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b.
c.
2.
124
To sharpen your pencil. Put your pencil in the sharpener.
2
Take a pencil and sharpener.
1
See if the pencil tip is sharp enough.
4
Turn the pencil inside the sharpener.
3
For going to school Put on your school uniform.
4
Take your breakfast.
3
Complete homework.
1
Go to school.
6
Take a bath.
2
Get on the school bus.
5
Write down the steps for the following tasks: a.
To turn on the computer.
b.
To shut down the computer.
c.
To eat a banana.
d.
To brush teeth.
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Chapter
11
INTRODUCTION TO LOGO PROGRAM
LOGO is the simplest programming language specially designed for children. LOGO stands for Language of Graphics Oriented. By using this language, you can instruct the computer to draw pictures to write text and to do calculations. You can have lots of fun with LOGO. LOGO was designed by Seymour Papert and Wally Feurzeig at the Massachusetts Institute, USA.
Starting MSWLOGO Microsoft Windows LOGO is latest version of LOGO for the use with Microsoft windows. To start MSWLOGO, follow the given steps. [Note: First install the MSWLOGO in your computer and switch on it] Step 1. Click on start button on the task bar. Step 2: Search the MSWLOGO program move the pointer to it. Step 3: Click / Double click on it. Now MSWLOGO Screen appears as:
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Different parts of LOGO screen Title bar
Control buttons
Menu bar
Graphic screen
Scroll bar Turtle
Command output box
Enter
Command input box
Title bar: The title bar appears at the top of LOGO windows screen which gives the program name and file name. Menu bar: The menu bar appears just below the title bar which contains different menus such as File, Bitmap, Set, Zoom etc. Graphics screen: The LOGO graphics screen is the working area where pictures and shapes are drawn. The small triangle shaped object present at the center of graphics screen is called Turtle. Commander window: The lower part of sub-window is called commander window. The LOGO commands are given in this window to the turtle for drawing different shapes and figures. The commander window is divided into two types. They are: Command input box: This is the part of commander window or area where logo commands are typed. Recall List box: This is the area or part of commander window which keeps the track of all the commands that are executed. 126
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Turtle: This is a small triangular shaped object that follows the LOGO commands entered and displays the related figure. Control buttons: The control button is seen at the extreme right of the title bar. This part of LOGO screen contains three different buttons such as minimize button, restore button and maximize button to control the size of screen. Scroll bar: This part of LOGO screen is seen at the extreme right of graphics screen which is used to move the screen vertically up and down.
LOGO Commands LOGO commands are the set of instructions that are given to the turtle for drawing specific figure or shape. The LOGO commands are collectively known as primitives. The commander window is the area where logo commands are typed. To execute LOGO commands, you need to press, enter key after the end of every command. [The extension of LOGO program file is .lgo] The commonly used LOGO commands are discussed briefly below. 1.
FORWARD or FD command This command is used to move the turtle in the forward direction step by step for the number of times specified. The general format of FORWARD command is : FORWARD or FD
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Example: FD 50
2.
Output:
BACK or BK command This command is used to move the turtle in the backward direction for the number of times specified. The general format of BACK command is BACK or BK
Example: BK 40
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Output:
3.
RIGHT or RT command This command is used to turn or rotate the turtle towards the right direction according to number of degrees specified. The number of degree can range from 0 to 360. The general format of RIGHT command is RIGHT or RT
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