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Input devices
“Input devices” are devices used to assign instructions and data to a personal computer.
Several types of input devices are summarized below.
Type
Reference
Nam
Input device
for characters and
numbers
Keyboard
A standard device for inputting characters, numbers, and symbols, by pressing the keys positioned
on the keyboard.
Pointing
devices
Mouse
A typical pointing device for inputting positional information such as icons, by rotating a mouse ball to
move the pointer on the screen. There is also an
“optical mouse” that detects reflected light to gauge
the amount of movement.
Trackball
A device for inputting positional information such as
icons, by rotating a ball using the fingers.
Trackpad
(Touchpad)
A device that moves a mouse pointer by brushing a
finger against a flat, plastic surface. It detects
changes in capacitance when a finger brushes
against the trackpad. Unlike a trackball or mouse,
no mechanical parts are used, making it resistant to
breaking. Mainly used on notebook computers.
Pointing stick
A device that moves a mouse pointer, by using a
finger to apply pressure forward/backward/left/right
against a stick that protrudes from the middle of a
keyboard. The speed at which the mouse pointer is
moved can be typically controlled by adjusting the
force used to press the stick. Mainly used on notebook computers. Names vary by manufacturer.
Digitizer/
tablet
A device that uses a coordinate indicator to input a
position on a flat surface. It is used to input design
plans and drawings. A “tablet” is a small version of
this device that is used on desk. A “stylus pen” is
used for input.
Touch panel
(Touch
screen)
A device that inputs data by touching the fingers
against icons or buttons shown on the display.
Used for bank ATM and library information displays,
etc.
Pointing device
A “pointing device” broadly refers to a
device that inputs positional information
(coordinate information) for the screen.
Reference
Stylus pen
A “stylus pen” is an input device that is
shaped like a pen. It is used to input
graphic objects and characters on a
tablet or PDA.
Description
Trackball
Trackpad
Pointing stick
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