The document provides information about computers and their components. It defines a computer as an electronic machine that accepts data from the user, processes it, and generates output. The main components of a CPU are the arithmetic logic unit (ALU) and control unit. The ALU performs arithmetic and logical operations on data, while the control unit controls instruction execution, data flow, and timing. Memory is used to store the data and instructions needed by the CPU and comes in primary forms like RAM and ROM, as well as secondary storage like hard disks. Input devices provide data to the computer and output devices receive processed data from the computer.

1. SAMACHEER-KALVI
COMPUTER SCIENCE
VOLUME-I
HIGHER SECONDARY FIRST YEAR

2. CHAPTER 1
Introduction to
Computers
Short Answers

3. 1. What is a computer?
Ans:
 A computer is an electronic machine data
from the user, processes the data by
performing calculations and operations on
it and generates the desired output as a
result.
 The term computer is derived from the
Latin word ‘computare’ which means ‘to
compute’

4. 2. Distinguish between data and
information.
Hence data are:
 Stored facts
 Inactive
 Technology based
 Gathered from various sources
Data: Data is defined as an unprocessed
collection of raw facts, suitable for
communication, interpretation or
processing.

5. Information: is a collection of facts from
which conclusions may be drawn. Data that
has been interpreted, translated, or transformed
to reveal the underlying meaning. This
information can be represented in textual,
numerical, graphic, cartographic, narrative, or
audiovisual forms.
Hence information is:
 Processed facts
 Active
 Business based
 Transformed from data.

6. 3.What are the components of
a CPU?
Ans:

7.  CPU is the major component
which interprets and executes software
instructions.
 It also control the operation of all other
components such as memory
 Input and Output units.
 It accepts binary data as input, process
the data according to the instructions
and provide the result as output.
 arithmetic logic unit (ALU).
 control unit .

8. 4. What is the function of an ALU?
Ans:
 The ALU is a part of the CPU where various
computing functions are performed on data.
 The ALU performs arithmetic operations
such as.
 Addition.
 Subtraction.
 Multiplication
 Division and logical operations.

9. 5. Write the functions of control unit.
Ans:
 Controls sequential instruction execution
 Interprets instructions
 Guides data flow through different
computer areas.
 Regulates and controls processor timing.
 Sends and receives control signals from
other computer devices.
 Handles multiple tasks, such as fetching,
decoding, execution handling and storing
results.

10. 6.What is the function of memory?
Ans:
The computer memory is a temporary storage
area. It holds the data and instructions that the
Central Processing Unit (CPU) needs. Before a
program can run, the program is loaded from
some storage medium into the memory. This
allows the CPU direct access to the program.
Read only memory(ROM).
Random access memory(RAM).

11. INPUT UNIT
 The input unit gets the
idea and program from
various input devices.
 The data is provided
through input devices
such as key keyboard,
Mouse
Track ball and joystick.
 Input data can also
provided by scanning
images, voice recording,
video recording etc ,…
OUTPUT UNIT
 The output unit gets the
processed data from
computer and sends it to
output devices to make
them available for the
user of computer.
 The output data is
provided through output
devices like display
screen, printer , plotter and
speaker

12. Primary memory
 This is temporary
memory.
Under primary memory
have two types:
 RAM
 ROM
It is also called main
memory.
Secondary memory
This is permanent
memory.
Under secondary
memory have
Hard disk
Compact disk(CD)
Floppy disk.
It is also called storage
memory.

13. Thanks