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Joystick
Joystick is a pointing device whose function is similar to a mouse, except that a mouse pointer
stops moving on the screen as soon as the user stops moving it, while the joystick pointer
continues to move in the direction towards which the joystick has been pointed. To stop the
pointer, the user has to bring the joystick to its upright position. It is generally used to play
video games.
Scanner
A scanner is a device that scans a document by sensing the reflection that is received when
the scanner emits rays on the contents. It takes the image of contents and converts it into
a digital file. The scanned image or photo can be stored in a computer and easily transferred
to a secondary storage device. Scanners can be categorised as Handheld scanners and
Flatbed scanners.
Optical Mark Reader (OMR)
OMR is an input device that can detect the marks on a paper. It is used to evaluate
answer sheets in which selected answers are marked in dark circles. It is used to read
the given or marked answers by sensing the marks made on the answer sheet.
Magnetic Ink Character Reader (MICR)
MICR is a device that is used by banks to process cheques by interpreting information stored
in MICR code. On the cheques, the name of the bank, branch code and cheque number are
printed with a special kind of ink containing magnetic particles or iron oxide which is scanned
& read with the help of MICR and accordingly processed by the computer. A MICR code
consists of nine digits that identify the bank and branch. On the back of credit/debit cards,
there is a thin black stripe (known as a magnetic stripe). Such stripes contain coded information in the form
of magnetic marks and are read when the card is inserted into the ATM.
Light Pen
Light Pen is a pen-like device which uses a light-sensitive detector to select or draw objects on the display
screen. It is similar to a mouse, except that with a light pen one can move the pointer on the screen by
touching it on the objects on the screen. When the pen is moved across the screen, its position is sensed
because of the light it emits.
Barcode Reader
Barcode Reader is a popular scanning device that reads the bar codes. Bar codes comprise
adjacent vertical black bars of different widths. Each bar in barcodes represent different
numbers. One can see the bar code on the back cover of this book as well. A bar code reader
emits a beam of light (laser beam), which reflects the bar code image. A light-sensitive detector
is present in the bar code reader which identifies and reads the bar code image. The bar pattern
is changed into numeric code inside the CPU.
Microphone
Microphone is a voice-based input device. With the help of this device, sound or voice is recognised/
recorded in the computer and is converted into digital form which is then played or processed by
the computer.
ICT Skills-I 49

