I/O devices allow communication between a computer and the outside world by allowing data to be input into the computer from external sources and for processed data to be output from the computer. Input devices include keyboards, mice, optical mark readers, joysticks, magnetic ink character recognition readers, and bar code readers. Common output devices are monitors, speakers, and printers such as dot matrix, inkjet, daisy wheel, line, and laser printers which produce visual or audio output.

2. INTRODUCTION
I/O Devices provides the means of
communication between a computer
and outer world.They are used to enter
the outside world into primary storage
and supply results after processing
from primary storage to user.

3. INPUT DEVICES
Devices which are used to insert the data
and information into the computer are called
“INPUT DEVICES”.
Some of the input devices are:
• Keyboard
• Mouse
• OMR
• Joystick
• MICR
• Bar code reader

4. KEYBOARD
Keyboard is the most commonly
used input device and it was invented
by “CHRISTOPHER LATHAM
SHOLES”. It has 101-keys (QWERTY),
with Alphabets from A to Z ,Number
keys 0-9, Functions keys (F1 to F12)
and keys like ‘ENTER’ key, ‘SPACE BAR’
key, ‘alt’ keys, ‘ctrl’ keys and
‘BACKSPACE’ keys.

5. KEYBOARD

6. MOUSE
Mouse is used to point to and select a
graphic icon or
menu items displayed on the GUI of the
screen.Father of mouse
was “DOUGLAS ENGELBART”. It has two
buttons and
a track wheel in between the buttons. Left
key is pressed
twice rapidly to start the program, and right
key is pressed once

8. OMR
OMR stands for Optical Mark Reader. A
scanner capable
of recognizing pre-specified types of mark
by pencil or pen.
It is a technique used for recognization of
marks involving
focusing light on the page being scanned
and detecting the
reflected light pattern from the marks.

9. JOYSTICK
Joystick is a pointing device to make the
movement of the
spherical ball easier.This device is used for
playing video games,
Flight simulatiors,training simulators and for
controlling robots.

11. MICR
MICR stands for Magnetic Ink Character
Recognition. MICR is used in banking industry for
faster processing
of large volume of cheaques.

12. BAR CODE READER
Bar Code Reader (BCR) is used for reading
(decoding) bar-Coded data.Bar code
represents alphanumeric data by the
combination of horizontal lines printed on the
products. Universal Product Code (UPC) is
the most widely known Bar Coding System.

13. OUTPUT DEVICES
• An output device is any piece of computer
hardware equipment used to communicate
the results of data processing carried out
by a computer which converts the
electronically generated information into
human readable form.
Commonly used output devices are:
 Monitors
 Speakers
 Printers

14. MONITOR
Monitor are most popular output device used
today for producing soft copy output. They
display the generated output on a television
like screen.
Types of Monitor:
 CRT (CATHODE RAY TUBE)
 LCD(LIQUID CRYSTAL DISPLAY)
 LED(LIGHT EMITTING DIODE)

16. SPEAKERS
Speakers are used to get output of the
sounds which are played on the computer
system.”Altec Lansing” invented the first
computer speakers in 1990.

18. PRINTER
Printers are the most commonly used device
today for producing
hard copy output.
Types of Printers:
 Dot matrix printer
 Ink jet printer
 Daisy wheel printer
 Line printer
 Laser printer

19. Different types of printers

20. PROJECTOR
Projector is an output device which is used
to project information from a computer on to
a large screen, it can be viewed by a large
number of people.This device is very useful
for making presentation to a large group of
peoples.

22. ?
QUESTIONS