The word ‘ computer has been derived from the Latin word ‘computer’, which means ‘to calculate ‘.A computer is an electronic device that manipulates information or data according to the of instructions called program

2. INTRODUCTION
TO
COMPUTER
 The word ‘ computer has been
derived from the Latin word
‘computer’, which means ‘to
calculate ‘.A computer is an
electronic device that
manipulates information or
data according to the of
instructions called programs.
It has the ability to store,
retrieve and process data .

3. FUNCTION OF COMPUTER
 Input information or data that is entered into a computer is called input .It sends
data and instructions to the central processing unit(CPU).
Processing It is the sequence of actions taken on data to convert it into information
which is meaningful to the user.
 Output It makes processed data available to the user.It is mainly used to display the desired
result to the user as per input instruction.
 Storage It stores data and programs permanently. It is used to store information
during the time of program execution and possible to get any type of information from
it.

4. Features of computer
 Speed The computer can process data very fast at rate of millions of instructions per second.
 Accuracy Computer provide a high degree of accuracy. They respond to the user as per the
input instructions.
 Storage Capacity Computer s are capable to store huge amount of data ,which depends on
the capacity of hard disk
 Versatility Computer can do different type of work simultaneously.
 Diligence Unlink human beings, a computer is from monotony, tiredness/lack of
concentration,etc.and can work for hours without creating any errors.
 Secrecy Leakage of information is reduced by creating login system with password
protection.
 Reliability Computers are more reliable than human beings .computer always
produce exact results.
 Plug and play Computers have the ability to automatically configure a new hardware and
software components.

5. COMPUTER HARDWARE
Computer hardware refers to the physical components of a computer that can be seen and touched
by the user.
Input Devices
An input device can be defined as an electro-mechanical device that allows the user to feed data into
the computer .
Keyboard
Keyboard is used to enter data or information in a
computer system, which may be in numeric from or
alphabetic from. When key is pressed, keyboard
interacts with a keyboard controller stores the code of
pressed buffer. Keyboard controller stores the code of
pressed key in keyboard buffer.

6. Mouse
Mouse is a small handheld
pointing device having two
buttons on its upper side and
also has a small wheel between
these buttons. It was invented
by douglas Engelbart at
stanford research centre in
1963.

7. Biometric Sensor
Biometric sensor is a device which recognises physical traits of the individual
.Biometric sensor s are used for marking attendance of employees /student in
organisations/institutions.
Scanner
Scanner is an optical input device which uses light as an input source on the
convert an image into an electronic from that can be stored on the computer. It is
used to convert the data and image on paper into the digital from.

8. Printer
A printer prints
information and data
from the computer onto
a paper . It can print
documents in color as
well as in black and
white . The quality of a
printer is determined by
the clarity of the print.

9. Speaker
It is an output device that
receives sound in the from
of electric current. It needs
a sound card connected to
aCPU,that generates
sound. These are attached
internally or externally to a
computer system .These are
used for listening music,
for being audible in
seminars during
presentations,etc.

10. Webcam (Web camera)
It is a video capturing device. Webcam is a digital camera attached to computer and
can be used for video conferencing ,Online chatting etc.
Webcam with computer webcam
Now –a- days , webcams are either embedded into the display with laptop/computer
or connected via USB or fire wire port or Wi-Fi to the computer.