CHAPTER 1
Introduction to Computer System
Computer Overview
Computers are being used in our
daily lives. Millions of computers are being used in all areas of modern age. All the computers are being
more advanced. They are used to process the data quickly and accurately. They
are being used in almost all difficult works due to their accuracy, speed, and
reliability. If all the computers in the world stopped working, there would be
disaster in the world.
A computer is an
electronic machine. It helps to enter data, process it, store it and produce
meaningful information. It carries out
calculations and other processes by following a set of instructions, called
program. The brain of the computer called CPU (Central Processing Unit) also
gives a hoot that has some who have added that movement of the home that this
overview of the design of the listed on the U.S. and the answer, as a vehicle
is of more than its facility half a dozen via whom live once the envy of the
hosts and the system didn’t mean the end of may be the envy that includes all
of the five of them on ter I have to do that I have s called CPU. It processes
all the input and instruction given by users and it also controls entire
operation of the computer system.
Functions of computer
A computer can perform
many tasks. Some of the functions are as
follow:
1.
Printing books,
articles, newspaper, etc.
2.
Maintaining accounts
in various organizations.
3.
Typing
documents and playing games.
4.
Watching video
and listening to songs.
5.
Downloading
files, software, etc.
Data and
Information
Data
Data is the collection of
information which is unorganized. It does not provide clear meaning. It can be
any name, sentence or number.
Information
The result which comes
after processing the data is called information. It is always useful to a user
and is used in decision making. The data without processing is meaningless.
Data 👉 It is processed
👉 Information
Input,
Processing and Output
A computer is a machine
that performs three types of functions. They are:-
Input
The data and
instruction given to the computer for performing task is called input. Data and instructions are given to the computer
through input devices like keyboard, mouse, etc. These input devices receive
the data from the user and send it to the CPU to process it.
Processing
The action
performed after taking instruction and to give output is called processing. The processing of computer is done in the CPU of a
computer.
Output
The result given after processing the data is called output. The meaningful
result is passed on to the user through output devices such as monitor or
printer.
Example of
input, processing and output is presented below:-
|
Picture(Input)
|
Machine(processing)
|
Printed(Output)
|
Star
|
Printer
|
|
Parts of a Computer System
The parts of a computer
are given below:-
Hardware
The physical parts of a
computer which can be touched and seen with our naked eyes is called hardware.
These hardware devices are mainly used to give instructions and take result
from the compute. Some name of the hardware devices are keyboard, monitor,
mouse, scanner, etc.
Software
The non-touchable part of
computer system which cannot be touched but can be seen with our naked eyes is
called software. It is formed by a set of instructions called program. It tells
a computer what to do and how to do.
CHARACTERISTICS OF THE COMPUTERS
The characteristics of the
computer are given below:-
Speed
A computer can perform
various tasks at a very high speed. It can solve complex task within a short
time which may take many year for humans to solve it. The speed of the computer
is measured in terms of milliseconds, microseconds, nanoseconds or picoseconds.
It takes fraction of seconds to perform a task by computer. The given table
shows the measurement of a computer:-
|
Unit of time
|
Symbol
|
Part of second
|
Meaning
|
|
Millisecond
|
Ms.
|
1/1000
|
One thousandth of a second
|
|
Microsecond
|
µs
|
1/1000000
|
one millionth of a second
|
|
Nanosecond
|
Ns
|
1/1000000000
|
one billionth of a second
|
|
Pico second
|
Ps
|
1/1000000000000
|
one trillionth of a second
|
Accuracy and Reliability
A computer basically gives
100% accurate result. But if we give wrong instruction to a computer, it might
not process the data or process it and give wrong result. This is also known as
GIGO (Garbage In Garbage Out). The output/ result depends on the given input/
instruction.
Versatile
It is the most wonderful
thing about the computer. The computer is a flexible machine and its use is not
limited to any single task. We use to perform task such as preparing
examination result, electricity bill, document, presentation, etc. It has great
capability to perform multiples task at a time. In this fast developing world,
we will hardly be able to see the sector where computer is not in use. So, we
can say that it is a versatile machine since it is used in many sectors of the
world.
Diligence
A computer can perform
many tasks continuously at the same speed, accurately and efficiently without
getting tired and bored. Due to this reason, computer is also called diligent
machine. Example: - if huge amount of calculations are to be done, a computer
will perform every calculations at a same instant of time without getting tired
and bored. So computer is a diligent machine.
Storage Capacity
A computer can store a
large amount of data and information which can be retrieved whenever required.
This large storage capacity is achieved through auxiliary storage in computer.
Storage capacity of computer is measured in terms bits, bytes, kilobytes,
terabytes, megabytes or gigabytes, etc.
No Intelligence
A computer is a dumb
machine and it cannot do any work without taking the instruction from the user.
It performs instructions at a wonderful speed and with 100% accuracy. It is you
to decide what you want to do and in what sequence. So a computer cannot take
decision like humans to perform task.
No Feeling
Computer does not have
feelings, emotions, taste, experience and knowledge. Therefore it does not get
tired and bored even after performing many tasks for long period of time. It
does not discriminate between users.
1. Fill in the blanks:
a. _________ is a brain of computer.
b. _________ is an electronic machine.
c. The ________ given after processing data is
called _____________.
d. A computer is a machine that performs _______
types of functions.
e. The result which comes after processing the
data is called__________.
f. Computer never gets tired and __________.
g.
Computer is used in almost each ________ work of the world.
2.
Match the following:-
Column ''A''
Column "B"
1024
byte
Use of computer is not limited to any single task
Storage
capacity
1 KB
Diligence
Store a large amount data and
information
No
feeling 1 TB
No
intelligence never
gets tired and bored
1024
GB Does not have emotion, taste
and knowledge
Versatile Dumb machine
3. Answer
these questions:
a. ~What is a
computer?
b. ~Define:
i) Data ii) Information
c. ~What do you
mean by input, processing and output?
d. ~Write any three
differences between data and information.
e. ~Write two
functions of CPU.
f. ~Write down
three characteristics of computer? Explain each.
g. ~Show the
measurement of speed of computer in a table.
h. ~Define the
following terms:
i)
Versatile
ii)
Accuracy and
Reliability
iii)
Storage
capacity of computer
iv)
No Feeling
v)
Diligence
i. ~Show the
measurement of storage capacity of computer in a
table.
j. ~Draw a table
and write the units of measurement of speed.
Comments
Post a Comment