Input devices such as keyboards, mice, joysticks, light pens, and trackballs are used to provide data and control signals to computers. Keyboards allow text input and contain 104-105 keys laid out like a typewriter. Mice are popular pointing devices with left and right buttons used to control cursor position but not enter text. Other pointing devices include joysticks and light pens. Trackballs are upside-down mice located in front of laptop keyboards. Output devices like monitors, printers, and projectors receive computer data and translate it into visual, audio, textual, or printed forms for users.

1. INPUT AND OUTPUT DEVICES
Prepared by
V.SANTHI
Assistant Professor,
Department of Computer Applications,
Thanjavur
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2. In computing an input device is a piece of
equipment used to provide data and control
signals to an information processing
system,such as a computer or information
appliance.
Input Devices

3. Examples of input device
► Keyboard
► Mouse
► Joystick
► Light pen
► Track ball
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4. 1. KEYBOARD
► Keyboard is the most common and very popular input
device which help to input
data to the computer.
► The layout of the keyboard is like to
traditional typewriter.
► 1o4 or 105 keys are available
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5. 2.MOUSE
► Mouse is the most popular pointing device.
►Generally it has two buttons called the left
and the right buttons
►A mouse can be used to control the position of
the cursor on the screen,but it cannot be used to
enter text into the computer.
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6. 3.JOYSTICK
► Joystick is also a pointing device which is used
to move the cursor position on a monitor screen.
► It is a stick having a special ball at its both
lower and upper ends.
► The lower sperical ball moves in a socket
► The joystick can be moved in all 4 direction.
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7. 4.LIGHTPEN
► Light pen is a pointing device similar to a Pen.
► It is used to select a displayed menu
item are draw picture on the monitor screen.
► It consists of a photocell and on
optical system placed in a small tube.
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8. 5.TRACKBALL
► A track ball is a computer cursor control device
used in many notebook and laptop computer.
► The track ball is usually located in front of the
keyboard toward user.
► Essentialy ,the track ball is a upside- down mouse
that rotates in place within a socket.
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9. Output devices:
► An output devices is a piece of computer
hardware that receive data from a computer and
then translate that data into another form.than
form may be audio , visual,textual,or hardcopy
such as a printed document
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10. Examples of output devices
► Monitor
► Printer
► Projector
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11. 1. MONITOR
► A monitor consists of a screen,circuitry,a power supply,buttons to
adjust screen
. setting and a casing that contains all of these
components
►A monitor display data from a computer
on to a screen so the user can interact
with the data via a digital interface
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12. 2.PRINTER
► The function of a printer is to create a
copy of whatever is sent from the computer to the printer.
► Printers take electronic data sent
from a computer and generate a hard copy.
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13. 3.PROJECTOR
►As it’s name suggest,
this output devices
‘ projects’computer images
are video
onto a wall or screen.
►Popular brands:BenQ,
sony,optima,epson
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