computer book 2 final for ctp 2076

New

Gateway to
Computer Science

A Complete Text Book of Computer Science

Authors : Dinesh Adhikari, Dilendra Bhatta

Contributing Co-authors : Laxman Adhikari, Toyaram Giri
Arjun Poudel

Layout Design : Zeeta Computer Service Pvt. Ltd.

(Samin R. Dhungana) Ghantaghar,

Kathmandu, Nepal

Copyright © : Publisher

Edition : 2075

Publication : Shubharambha Publication Pvt. Ltd.
Kathmandu, Nepal

Preface Contents

Along with the evolution of human Unit 1
beings new thoughts, area of knowledge
and technology also developed together. 1. The Electronic Era!
Among the eruptions, ICT (Information
and Communication Technology) is 2. Learning Computer 12
one which has unquestionably become
important part of human beings. A 3. Features of Computer 25
person is not better than a caged pigeon
if s/he is far from computer technology 4. Components of Computer 32
in this century. New Gateway to
Computer Science Book-2 is a 5.. Working with Mouse 46
complete package which obviously
supports a lot to the students as this is 6. Uses of Computer 56
one of the most useful Text Book, so
far available in the market. This book 7. Starting a Computer 65
is completely prepared considering the
level of the students. This text has the 8. Working with Paint Brush 72
various salient features like it focus on
child psychology, inclusion of comic’s Quiz Section 95
cartoons, conversation based, focus
on pictorial descriptions,quiz section, My Worksheets 99
worksheets, etc.
Guidelines to the teachers 110
Comments and constructive suggestions
are highly welcomed from the readers
and professionals to update this text
book.

Suggest us:

[email protected]

Thank you.

Unit : 1

The Electronic Era!

Note to Teacher

Ask the following questions to the students in class
before starting the lesson and collect the answer.
Do you have radio and television at your home?
Do you have calculator at your home?
Do you have telephone set at your home?
Do your parents have a mobile phone?
Do you have a computer set at your home?
Do your parents have a laptop?

New Gateway to Computer Science Book - Two 1

Dear students,
you are welcome to grade
two. In this class also,you
are going to learn about the
computer. Let’s begin the
chapter with the name of some electronic

devices.

Look at the given pictures carefully.

Mobile Radio Computer

Television Tablet Refrigerator

2 New Gateway to Computer Science Book - Two

Let’s Read!

As we discussed in
previous class, all the
devices that you see
in the above shown
figures like radio,
television, calculator,
telephone, mobile,
computer set, laptop,
etc. are the electronic
devices. Electronic
devices are very important in this digital age. The
electronic devices are the integral part of humans
these days.

Electronic devices are those devices that can work
only with the electricity or with the source of
electric power. It is a man-made tool designed to
make our work easier.

Note to the Teacher
Ask the following questions to the students in class
and discuss on the followings.

New Gateway to Computer Science Book - Two 3

Does a radio work without battery or electricity?
Does a television work without electricity?
Does a computer work without electricity?
Does a mobile work without battery?

Here, all the devices that we discussed above need

source of electric power

to work. For example,

a radio can work

with battery or with

electricity. A television

can work with the help of

electricity. A computer

needs electricity to work.

A mobile phone also needs

battery to work. We can say Tips Corner!
that battery is a source of
electricity to work which you Alexander Graham
Bell was the inventor
of telephone.

can use on the radio, mobile,

tablet, calculator, etc. The devices which work with

the help of electricity are called the electronic

devices.

4 New Gateway to Computer Science Book - Two

A computer can not be operated without electricity.
Therefore, it is called an electronic device.

Student's Activity

Observe the electronic devices
such as rice cooker, fan, television,
refrigerator, ceiling fan, heater, etc.
with the help of your parents and find how they
are connected with electric plug.

Some electronic devices and non-electronic objects
Electronic Devices

Mobile Radio Computer

Television Tablet Refrigerator

New Gateway to Computer Science Book - Two 5

Non-Electronic objects

Tree Table Ruler

Book Sofa Bed

Oral Evaluation

yy Name any four electronic devices.
yy What is an electronic device?
yy Does a television need electricity to work?
yy What is the source of power for a calculator?
yy Is the computer an electronic device?
yy Name any four non-electronic objects.
yy Tell the name of any six electronic devices that

you have at your home.

6 New Gateway to Computer Science Book - Two

Revision Time
áá Mobile, Calculator, Radio, Television etc. are

the electronic devices.
áá The electronic devices are the integral part

of human these days.
áá Electronic devices need electricity to work.
áá Electronic devices are man-made tool which

helps to do our work easily.
áá Battery is also a source of power in most of

the electronic devices.
áá A computer can not work without electricity.
áá Non-electronic objects do not need electricity

to work.

Project Work

Prepare a chart paper with the pictures of
electronic devices that you have at your home
and submit it to your subject teacher.

New Gateway to Computer Science Book - Two 7

Evaluation Time

1. Re-arrange the following letters and make a
suitable word.

a. ADIRO : …………...........................................

b. CTLOCLUAAR : …………...........................................

c. OMLIBE : …………...........................................

d. LTOEEIVSIN : …………...........................................

2. Name the following electronic devices.





8 New Gateway to Computer Science Book - Two

3. Write Yes, it is or No, it is not for the following
statements.

a. Is a television an electronic device?

Ans : ...........................................................................................................................................................................................................................................

b. Are shoes electronic objects?

Ans : ...........................................................................................................................................................................................................................................

c. Is a mobile an electronic device?

Ans : ...........................................................................................................................................................................................................................................

d. Is a calculator an electronic device?

Ans : ...........................................................................................................................................................................................................................................

e. Is a laptop an electronic device?

Ans : ...........................................................................................................................................................................................................................................

f. Does a radio need electricity to work?

Ans : ...........................................................................................................................................................................................................................................

New Gateway to Computer Science Book - Two 9

4. Match the following electronic devices with
their names.

Calculator

Laptop

Tablet

Television

Mobile


10 New Gateway to Computer Science Book - Two

5. Name any four electronic devices that are
used at your home.

................................................................................................................. .................................................................................................................

................................................................................................................. .................................................................................................................

6. Write True for correct and False for the
wrong statements.

a. Computer needs electricity to
work.

b. A tree needs electricity to grow up.

c. A table does not need electricity to
move.

d. Battery is the source of electricity.

e. A television is an electronic device.

f. A laptop and Tablet are same in size.

g. A calculator can work with battery.

h. A ceiling fan is not an electronic
object.

New Gateway to Computer Science Book - Two 11

Unit : 2

Learning Computer

Note to Teacher

Ask the following questions to the students in class
before starting the lesson and collect the answer.
Have you ever seen the computer?
Do you have a computer at your home?
Do you have a computer at your school?
Can you work with the computer?
Have you ever played games on computer?
Do you like to play games on the computer?
Do your family members use computer to watch

television?

12 New Gateway to Computer Science Book - Two

Dear students,
In previous class, you learnt
about some electronic devices
and non-electronic objects.
Among the various electronic
devices, we are going to learn
about the computer in this class. As you
know that the computer is very important
for us. You can see the use of computer

everywhere.

Observe the Pictures

New Gateway to Computer Science Book - Two 13

The pictures given above are the basic parts of the
computer system. Without these components, you
cannot work properly with the computer system.

Note to the Teacher
Make the children visit your computer lab and show
them the parts of a computer like mouse, keyboard,
system unit and monitor and also demonstrate them
how they are plugged with the electricity.

The individual parts of the computer make a
complete computer system so that you can work
easily with the computer system.

Tips Corner!

Abacus was the first
manual calculating
device.

All the individual parts of the computer are
connected with each other to work smoothly.

14 New Gateway to Computer Science Book - Two

Let’s Read!

The computer is called

an electronic device

because it cannot

work without the

help of electricity or

electric source. All

the individual parts

of the computer like

keyboard, mouse,

monitor and system

unit need electricity or

electric source to work. Remember that the mouse

and keyboard get electricity from the system unit.

They are not directly connected with the electric

plug. But the monitor and the system unit must be

plugged in directly with electricity.

Note to the Teacher

Demonstrate the source of electricity for mouse and
keyboard to the students.

New Gateway to Computer Science Book - Two 15

Conversation Time!
Read the following conversation and do the
activities that follows.

Kumar Karna and Lalita
Nepali are the best friends
of grade two. Both of
them are house partners
too. Kumar’s father has
a computer and Lalita’s
father has a mobile phone. Sometimes, Kumar goes
to Lalita’s room and plays games on her father’s
mobile and Lalita also goes to Kumar’s room and
watches movies on his father’s laptop.

It was a Saturday morning. Lalita was at Kumar’s
home and she was watching movies on the laptop.
At the same time, Kumar’s father came to the
room and saw that both of them were busy on
watching movies on the laptop.

16 New Gateway to Computer Science Book - Two

Hey Kids! What are
you doing here?

Papa! We are watching movie
now because today is Saturday.
We don’t have to go to school.

Yes! It’s ok, but only watching
movies on your holidays is not a
good habit. Kids! I am worried
about it.

Uncle! What can we do except
watching movies on the
computer?

New Gateway to Computer Science Book - Two 17

Listen! You can use it for drawing
and painting, typing, reading
books, news and so many other
things. So, never become busy on
watching movies only.

Thanks, uncle. We will obey you
and we will not watch movies
much. We will also do other
activities on the computer as
you have suggested us.

Do you know, students!
nowadays, the computer is
like an integral part of human.
Without it, people cannot work
properly. It can be used for various
purposes like for communication,
business, in hospital, medicine, science
and research, entertainment, etc.

18 New Gateway to Computer Science Book - Two

Oral Evaluation

yy Who are the best friends?
yy Whose father has a laptop and whose father has

a mobile?
yy What do Kumar and Lalita do on laptop mostly?
yy Why is Kumar's father worried?
yy What other things can be done with the help of

the computer?
yy Tell any two disadvantages of technology.
yy Name any four technological devices.

Project Work

¬¬ Prepare a chart paper with the pictures of
the mouse, keyboard and system unit then
submit it to your teacher.

¬¬ Draw the figure of monitor in A4 paper and
submit to your teacher.

New Gateway to Computer Science Book - Two 19

Revision Time

áá The monitor, system unit, mouse and the
keyboard are the basic tools to work with
computer system.

áá All the computer parts must be connected
properly to perform different functions.

áá The individual parts of the computer make a
complete computer system.

áá The computer is an electronic device because
it cannot work without electricity or source of
electricity.

áá The keyboard and mouse are not directly
connected to electricity. They can get
electricity from the system unit.

áá The computers can be used for communication.
áá The computers are also used for business and

research.
áá These days, computers are very useful at

hospitals. It can be used for X-Ray, CT scan etc.

20 New Gateway to Computer Science Book - Two

Evaluation Time

1. Re-arrange the following letters and make a
suitable word.

a. RKYEBOAD : ………….........................................

b. OMUES : ………….........................................

c. OONITRM : ………….........................................

d. SSYMTE UNIT : ………….........................................

2. Name the following devices.





New Gateway to Computer Science Book - Two 21

3. Match the following computer parts with
their pictures.

System unit

Monitor

Keyboard

Mouse


22 New Gateway to Computer Science Book - Two

4. Answer the following questions.

a. Name any four electronic devices:

…………......................................... ………….........................................

…………......................................... ………….........................................

b. Why is the computer called an electronic
machine?

............................................................................................................
c. From where do mouse and keyboard get their
electric energy?

............................................................................................................
d. Can you work with the computer without the
monitor?

............................................................................................................

e. According to Kumar’s father,for what purpose
can we use computer?

............................................................................................................

New Gateway to Computer Science Book - Two 23

f. Name the areas where the computers are
being used.

............................................................................................................

Project Work

Visit your computer lab and observe how the
computers are connected with each other. Also,
write the name of devices that are available in
your lab.

a. .....................................................

b. .....................................................

c. .....................................................

d. .....................................................

e. .....................................................

f. .....................................................

g. .....................................................

24 New Gateway to Computer Science Book - Two

Unit : 3

Features of Computer

Note to Teacher

Ask the following questions to the students in class
before starting the lesson and collect the answer.
Does a computer work fast?
Does a computer have storage device?
Does a computer need everywhere?
Does a computer get tried after long work

continuously?
Do you know what will happen if we do not use the

computer properly?

Speed Stor
age
Versatile

uracy
Features of
Computer

Diligence Acc

New Gateway to Computer Science Book - Two 25

Dear kids!
You are welcome to new
chapter. In this chapter, we
will discuss about the features
of the computer. You know, the
computer is an amazing machine.
Let’s learn why the computer is an amazing

machine for us.

Note to the Teacher
Here is a conversation between two students of a
class about the features of the computer. Make the
children do the following conversation in the class.

Hello Krisha! How are you
today? You look little sad, why?

I am fine but you know, I
have something in my mind.

What is that?
Please, tell me.

26 New Gateway to Computer Science Book - Two

In previous chapter and previous
class, our Dinesh sir told that the
computer is a very amazing device.
It is very important for us but how?

Oh! You are too worried about that.
You know my brother Ujjwal is a
computer teacher. He told me about
it yesterday at home. If you want to
listen, I will tell you some points.

Sure! Please tell me,
I want to listen.

Ok, I will
explain about it.

¬¬ The computer can work very fast so that we
can do our work very easily within a very short
period of time. It makes our work easier. It
has a great speed to work.

New Gateway to Computer Science Book - Two 27

¬¬ The Computer works with very fast speed without
any mistakes. So, it is an accurate machine.

¬¬ We can store many things in the computer like
pictures, videos, games, data, etc. So, it has
the capacity of storage.

¬¬ We may get tired after doing more work but the
computer never gets tired. So, it is a diligent
machine.

¬¬ It can be used everywhere at any time. So, it is
called a versatile machine.

Oh ! Thank you my friend. I am
so happy with you. You are my best
friend. Now, I will tell these things to

my father at home.

You are most welcome. You
are also my best friend.

28 New Gateway to Computer Science Book - Two

Oral Evaluation

yy Whose brother is a computer teacher?
yy Which device can work very fast?
yy Who wants to know about the features of the computer?
yy Who is explaining about the features of the

computer?

Evaluation Time

1. Write True for correct and False for wrong
statements.

a. The computer is a very useful
machine.

b. The computer can make our work
easier.

c. The computer cannot work fast.

d. The computer often gets tired.

e. The computer is a versatile machine
because it cannot be used everywhere.

f. Computer has a capacity of storage.

New Gateway to Computer Science Book - Two 29

2. Fill in the blanks with suitable word.

storage tired everywhere computer mistakes

a. A computer never gets ..........................

b. A ……………………. can work very easily and
faster.

c. A computer has a ………………… device to store
the data.

d. The computer works at a very high speed
without any ……………………

e. The computer can be used ...……………….. at
any time.

3. Answer the following questions:

a. Does a computer work very fast and easily?
......................................................................................................................

b. Why the computer is called an accurate
machine?

......................................................................................................................

......................................................................................................................

30 New Gateway to Computer Science Book - Two

c. Why is the computer called a versatile device?
......................................................................................................................

d. Can a computer store pictures and videos?
......................................................................................................................

e. Write any four features of a computer.
......................................................................................................................

......................................................................................................................

......................................................................................................................

......................................................................................................................

f. What can be stored on the storage devices?
......................................................................................................................
......................................................................................................................

g. Does a computer get tired?
......................................................................................................................

New Gateway to Computer Science Book - Two 31

Unit : 4
Components of
Computer

Note to Teacher

Make the children to visit the computer lab and
let them to observe the items available there.

Print some pictures of the monitor, mouse and the
keyboard then paste them in a chart paper and
demonstrate them in the class.

Let the students to do the conversation included
in this unit.

Ask the students to prepare a chart paper and
pasting the various pictures of the mouse, keyboard
and the monitor.

32 New Gateway to Computer Science Book - Two

Dear students,

as you know that human body
has various parts to function
properly. All the human body
parts are equally important
for us like eyes, hands, ears, brain,bone,
muscles, heart, kidney and so on. Like
this, the computer also has various parts
so that they can function properly. All

the parts are equally important for
the computer system.

Now, let’s discuss some important parts of the
computer

Monitor

The monitor and television
screen are almost similar in size.

It is an output device.
The monitor is used to display

the information on the screen.
The output displayed by monitor is called a soft

copy output.

New Gateway to Computer Science Book - Two 33

We can easily change the output displayed by
the monitor.

Student's Activity

After reading the above points, write
about the monitor in a paragraph.

Keyboard

The keyboard is a popular input device.
Without keyboard, we cannot type the text.
There are various alphanumeric and special

keys in the keyboard.
The alphabet keys range from

A to Z.
The numeric keys range from

0 to 9.
The function keys are F1, F2,

F3, …………F12.
Enter, Shift , Control, Del, etc. are the special

keys.

34 New Gateway to Computer Science Book - Two

Speaker

It is an audio output device.
It generates sound.
It gives temporary output.

Note to the Teacher
Bring different types of keyboard from the computer
lab and demonstrate them in class.

Keys of Keyboard
Alphabet Keys


Number keys and Keypad
Arrow keys

Function keys

Note to the Teacher
Ask the students to draw the figure of keyboard on
A4 size blank paper and paste them in the classroom
to decorate the class.

New Gateway to Computer Science Book - Two 35

Mouse

The device mouse
looks like a mouse.

The mouse is a small
handheld device.

It is called an input
pointing device.

You can click and point anywhere of the monitor
screen to select the items with the help of the
mouse.

It has two or three buttons.
It also has a scroll button.

Student's Activity

After reading the above points, write
about a mouse in a paragraph.

Note to the Teacher
Help the students to do the following conversation in
the class.

36 New Gateway to Computer Science Book - Two

Conversation Time!
Read the following conversation and do the
oral activities that follows.

Sima Magar and Bharat Tharu are two best friend
of the class. They are also good at their study.
When teacher comes to the class and starts
teaching new lesson, they listen to the teacher
very carefully and ask many questions to him.
Mr.Ramkrishna Nepali is their computer teacher.
He becomes very happy when the students ask
questions in the class.

Sir ! Can we work
without the monitor?

No, Sima. It’s impossible. You
must have a monitor to work with
the computer. If you do not have
monitor, you can not see the things
whatever you are doing.

New Gateway to Computer Science Book - Two 37

Sir, why is the monitor
called an output device?

I think, your friend Bharat
knows about it. Bharat! Can you
tell about it?

Sure, sir! I can tell about it. It is
called an output device because
it is used to display the things on
the screen so that we can see and
understand what the computer is
displaying.

Yes, you are correct.

38 New Gateway to Computer Science Book - Two

But sir, I have little confusion
about the monitor and keyboard.

Ok, do not worry, now its
turn of Sima to tell about it.

Sir, both mouse and keyboard are
the input devices. Mouse is a pointing
device but a keyboard is a typing
device. The mouse has two or three
buttons but the keyboard has various
keys. The various keys are alphabet
keys,numeric keys, special keys,
arrow keys, function keys, etc.

Thank you, Sima for your
good answer.

New Gateway to Computer Science Book - Two 39

Oral Evaluation

yy Can we work without monitor?
yy Is monitor an input device?
yy Are mouse and keyboard input device?
yy How many buttons does a mouse have?
yy Name any three keys of a keyboard.
yy Why is monitor an output device?

Let's Revise

áá Monitor is an output device which looks like a
television screen.

áá The output displayed by monitor is softcopy.
áá Softcopy output is changeable output.
áá Keyboard is an input typing device.
áá Keyboard has various keys like alphabet keys,

function keys, numeric keys and special keys.
áá Speakers are audio output devices.
áá Mouse is a small handheld pointing device.
áá Basically, a mouse has a three buttons.

40 New Gateway to Computer Science Book - Two

Evaluation Time

1. Circle the correct answer from the given
options.

a. A mouse is an …………..device.

i. input ii. output

b. A keyboard is an …………..device

i. input ii. output

c. A monitor is an ………………device

i. input ii. output

d. An output of the monitor is ………..

i. soft copy ii. hard copy

e. Generally a mouse has …………..
i. two or three buttons ii. five buttons

f. A , B, C , D, etc. are called ……………...
i. alphabet keys ii. number keys

g. Which of the following is a function key?

i. F3 ii. D1

h. Which of the following device is used to
produce sound?

i. Speaker ii. Monitor

New Gateway to Computer Science Book - Two 41

2. Re arrange the jumbled words.

a. NFNUCTOI KYES : ...........................................................

b. STFO COYP : ...........................................................

c. EPSCLAI SEYK : ...........................................................

d. SBUTNTO : ...........................................................

e. BKEOYRDAS : ...........................................................

f. PAKEERS : ...........................................................

3. Write True for correct and False for the
wrong statements.

a. The monitor is an input device.

b. The keyboard is a pointing device.

c. 1,2,3,4, etc. are called numeric
keys.

d. The F5 key is a function key.

e. The mouse is an output device.

f. A speaker is an audio input device.

42 New Gateway to Computer Science Book - Two

4. Match the following devices with their
pictures.

Audio Output

Soft copy output

Input device

Pointing device


5. Answer the given questions:

a. What is a mouse?
......................................................................................................................

New Gateway to Computer Science Book - Two 43

b. Define a keyboard.

......................................................................................................................

c. Name some keys of a keyboard.

......................................................................................................................
......................................................................................................................

d. Write down the name of any six function keys.
....................................................... .........................................................
....................................................... .........................................................
....................................................... .........................................................

e. Name any two input devices.
....................................................... .........................................................

f. Name the function of a keyboard.

......................................................................................................................

g. Which device is called soft copy output device?

......................................................................................................................

44 New Gateway to Computer Science Book - Two

Project Work

Visit your computer lab and observe the monitor,
mouse and keyboard in detail. Also, draw a picture of
the monitor and mouse in the space provided below.

Monitor

Mouse

New Gateway to Computer Science Book - Two 45

Unit : 5

Working With Mouse

Note to Teacher

Bring different types of mouse and demonstrate
in the class.

Prepare a chart paper with various types of mouse
and demonstrate them in class.

Demonstrate different action of the mouse in
computer lab.

46 New Gateway to Computer Science Book - Two

As you know that the mouse is a handheld input
pointing device,it is an essential part of the computer
system. The mouse lets you point objects on the
screen. You can simply click on them and move them.
All desktop computers need mouse to work.

Buttons of mouse:

Look at the given figure.

Scroll button
Right button

Left button

As in above figure, a mouse has two or three buttons.
The previous mouse used to have only two buttons
but nowadays, we can see the mouse with at least
three buttons. The mouse buttons are named as
right button , left button and scroll button.

There are some proper techniques for holding
a mouse.
Place your thumb on the desk or table top on

the left side of the mouse.

New Gateway to Computer Science Book - Two 47

Your index finger (pointer) should rest on the
left button of the mouse.

Place your middle finger
on the right button of
the mouse.

Your ring finger and
little finger should rest
on the right side of the
mouse.

Your palm should cup the end of the mouse
gently.

The base of your wrist should rest on the mouse
pad or the desktop.

Some mouse action:

A mouse has various actions. You can click,move,drag,
double click, right click, left click, scroll, etc. with
the mouse. Some of them are discussed below.

48 New Gateway to Computer Science Book - Two