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Input And Output
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Input is any data and instructions entered into the memory of a
computer.
Input Device is any hardware component that allows users to
enter data and instructions into a computer.
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Input Devices

Keyboard and pointing devices
pointing devices:
Mouse is a pointing device because it allows a user to control a pointer on the screen.
In GUI, a pointer is a small symbol on the screen whose location and shape change as a
user moves a pointing device.
a pointing device can select text, graphics and other objects and click buttons, icons, links
and menu commands.
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Input Devices Categories

Keyboard
Cable keyboard
Wireless keyboard
Mouse
Trackball
Mechanical
Optical
Touchpad
Input Devices
Pointing Stick
Light Pen
Pointing
Devices
Touch Screen
Optical Scanner
Pen Input
Optical Reader
Audio Input
Barcode Reader
Digital Camera
Scanner and
reading devices
RFID reader
MIRC reader
Magnetic strip card readers
Biometric Input
Physical
Behavioral
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Mouse

There are 2 types: mechanical mouse and Optical mouse.
 Mechanical mouse has a rubber or metal ball on its underside.
 You should place a mechanical mouse on a mouse pad.
 Mouse pad is a rectangular rubber or foam pad that provides better traction than the
top of a desk
 Optical mouse uses devices that emit and sense light to detect the mouse’s
movement.
 Some use optical sensors; other use laser.
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Trackball

Is a stationary pointing device with a ball on
its top or side, Similar to a mechanical
mouse that has a ball on the bottom.
 To move the pointer using a trackball,
you rotate the ball with your thumb,
fingers or the palm of your hand.
 It has one or more buttons that work
just like mouse buttons.
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Touchpad

Is a small, flat, rectangular pointing device that




is sensitive to pressure and motion.
To move the pointer, slide your fingertip
across the surface of the pad.
You also can tap the pad’s surface to
imitate mouse operations such as clicking.
Around the edge of the pad there are one
or more buttons that work like mouse
buttons.
Touchpad's are found most often on
notebook computers.
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Pointing Stick

Is a pressure-sensitive pointing device
shaped like a pencil eraser that is
positioned between keys on a
keyboard.
 To move the pointer you push the
pointing stick with a finger.
 IBM developed the pointing stick for its
notebook computers.
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Light Pen

Is a handheld pointing device that detect the
presence of light.
To select objects on the screen,
 a user press the light pen against the surface
of the screen
 or points the light pen at the screen and then
press a button on the pen.
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The Keyboard


Is an input device that contains keys users press to enter data and
instructions into a computer.




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Typing area
Numeric keypad
Function Keys
Media control buttons
Internet control
 Desktop computer keyboard often attach to the System Unit using


Cable: a serial port or USB port.
Without cables :Ir or Bluetooth
 Wireless keyboard or cordless keyboard, is a buttery-powered device
that transmits data using wireless technology
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Touch screen

Is a touch-sensitive display device.
 Users can interact with these
device by touching areas of the
screen.
 Because touch screens require a
lot of arm movements, you do not
enter large amounts of data using
a touch screen.
 Many handheld game consoles
have touch screens.
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Pen Input

Mobile users often enter data and
instructions with a pen-type device.
 With pen input ,users write, draw, and
tap on a flat surface to enter input.
 The surface maybe a monitor, a
screen, a special type of paper or
graphic tablet.
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Audio Input

Is the process of entering any sound into the computer such as
speech, music, and sound effects.
User enter sound into computer via devices such as
 microphones
 tape players
 CD/DVD players
 radios
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Other Types of Input

Digital Cameras
Allows users to take pictures and store the photographed
image digitally instead of on traditional film.
 They use internal flash memory to store images.
 Others store images on mobile storage media,
including a flash memory, memory stick and mini
CD/DVD.
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Digital Cameras

A
digital
camera's
resolution is defined in pixels.
 The greater the number of
pixels the camera uses to
capture an image, the better
the quality of the image.
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Scanners and Reading Devices

Some input devices save time
1.
2.
3.
4.
5.
6.
by capturing data directly
from a source document.
Optical scanner
Optical readers
Bar code readers
RFID readers
Magnetic strip card readers
Magnetic-ink character recognition reader.
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1- Optical scanner

Usually called a scanner
Is a light-sensing input device that reads printed text
and graphics and then translates the results into
a form the computer can process.
Many scanner include OCR ( optical character
recognition ) software, which can read and convert
text documents into electronic files.
OCR SW converts a scanned image into a text file that
can be edited.
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2- Optical Readers

Is a device that uses a light source to read characters, marks and
codes and then converts them into digital data that a computer can
process.
Two technologies used by optical readers are
A. Optical character recognition.
B. Optical mark recognition.
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A- Optical character
recognition (OCR)


Involves reading handwritten, typewritten or
printed text and translating the image into a
form the computer can process.
 Most OCR devices include a small optical
scanner for reading characters and sophisticated
SW to analyze what read.
 It range from large machines that can read
thousands of documents per minute to handheld
that read one document at a time.
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B- Optical mark recognition (OMR)
Devices read hand-drawn marks such as small circles or
rectangles.
One of the most familiar applications of optical mark recognition
is the use of pencil bubble optical answer sheets in multiple
choice question examinations.
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3- Bar Code Readers

also called bar code scanner
 is an electronic device that uses laser beams for
reading printed barcodes.
 Bar code is an identification code that consists of
set of vertical lines and spaces of different
widths.
 The bar code represent the data that identifies
the manufacturer and the item.
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4- RFID Readers

Radio-frequency identification readers
 is a technology that uses radio signals to
communicate with a tag placed in or attached to an
object, an animal, or a person.
 RFID tags, which contain a memory chip and an
antenna, are available in many shapes and size.
 RFID reader reads information on the tag via radio
waves. It can be handheld devices or mounted in a
stationary object such as a doorway.
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RFID Readers

 Many retailer see RFID as an
alternative to bar code identification
because it dose not require direct
contact or line-of-site transmission.
 Other uses of RFID include tracking
times of runners in a marathon;
tracking location of soldiers, and
airline baggage.
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5- Magnetic strip card
readers

Often called a magstripe reader
 Reads the Magnetic strip on the back of credit cards or
other similar cards.
 The strip contains information identifying you.
 Some information stored in the strip includes your name,
account number, the card expiration date, and a country
code.
 If the Magnetic strip card readers rejects your card, it is
possible that the Magnetic strip is scratched, dirty or
erased.
 Exposure to magnetic field can erase the contents of a
card’s magnetic stripe.
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6- MICR Reader
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Magnetic-ink character recognition
Devices read text printed with magnetized ink.
 MICR reader converts MIRC characters into a form the computer can
process.
 The banking industry almost exclusively uses MICR for check processing.
Bank routing no.
Account no.
Check no.
Check amount.
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Biometric Input

Is the technology of authenticating a person’s identity by
verifying a personal characteristic.
 Biometric devices grant users access to programs,
systems, or rooms by analyzing some physiological or
behavioral characteristic.
 such as fingerprints, eye patterns, voice patterns,
facial features, signatures and hand geometry.
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Biometric Input
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Fingerprint scanner
Face recognition system
Hand geometry system
Voice verification system
Signature verification
system
 Iris recognition system
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