Download pdf - Input Devices and Output Devices

8/3/2019 Input Devices and Output Devices

1/5

Input Devices:

Key board:

In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement ofbuttons orkeys, to act as mechanical levers or electronic switches. Following the decline

ofpunch cards andpaper tape, interaction via teleprinter-style keyboards became the

main input device for computers.

Despite the development of alternative input devices, such as the mouse, touchscreen,pen devices,character recognition and voice recognition, the keyboard remains the most

commonly used and most versatile device used for direct (human) input into computers.

A keyboard typically has characters engraved orprinted on the keys and each press of a

key typically corresponds to a single written symbol. However, to produce some symbolsrequires pressing and holding several keys simultaneously or in sequence. While most

keyboard keys produce letters, numbers or signs (characters), other keys or simultaneous

key presses can produce actions or computer commands.

Mouse:

In computing, a mouse is apointing device that functions by detecting two-dimensional

motion relative to its supporting surface. Physically, a mouse consists of an object held
http://en.wikipedia.org/wiki/Computinghttp://en.wikipedia.org/wiki/Typewriter#Keyboard_layouts:_.22QWERTY.22_and_othershttp://en.wikipedia.org/wiki/Push-buttonhttp://en.wikipedia.org/wiki/Punch_cardhttp://en.wikipedia.org/wiki/Paper_tapehttp://en.wikipedia.org/wiki/Teleprinterhttp://en.wikipedia.org/wiki/Input_devicehttp://en.wikipedia.org/wiki/Mouse_(computing)http://en.wikipedia.org/wiki/Touchscreenhttp://en.wikipedia.org/wiki/Pen_computinghttp://en.wikipedia.org/wiki/Character_recognitionhttp://en.wikipedia.org/wiki/Voice_recognitionhttp://en.wikipedia.org/wiki/Engravinghttp://en.wikipedia.org/wiki/Printinghttp://en.wikipedia.org/wiki/Symbolhttp://en.wikipedia.org/wiki/Letter_(alphabet)http://en.wikipedia.org/wiki/Numberhttp://en.wikipedia.org/wiki/Character_(computing)http://en.wikipedia.org/wiki/Computinghttp://en.wikipedia.org/wiki/Pointing_devicehttp://en.wikipedia.org/wiki/Two-dimensionalhttp://en.wikipedia.org/wiki/Computinghttp://en.wikipedia.org/wiki/Typewriter#Keyboard_layouts:_.22QWERTY.22_and_othershttp://en.wikipedia.org/wiki/Push-buttonhttp://en.wikipedia.org/wiki/Punch_cardhttp://en.wikipedia.org/wiki/Paper_tapehttp://en.wikipedia.org/wiki/Teleprinterhttp://en.wikipedia.org/wiki/Input_devicehttp://en.wikipedia.org/wiki/Mouse_(computing)http://en.wikipedia.org/wiki/Touchscreenhttp://en.wikipedia.org/wiki/Pen_computinghttp://en.wikipedia.org/wiki/Character_recognitionhttp://en.wikipedia.org/wiki/Voice_recognitionhttp://en.wikipedia.org/wiki/Engravinghttp://en.wikipedia.org/wiki/Printinghttp://en.wikipedia.org/wiki/Symbolhttp://en.wikipedia.org/wiki/Letter_(alphabet)http://en.wikipedia.org/wiki/Numberhttp://en.wikipedia.org/wiki/Character_(computing)http://en.wikipedia.org/wiki/Computinghttp://en.wikipedia.org/wiki/Pointing_devicehttp://en.wikipedia.org/wiki/Two-dimensional


2/5

under one of the user's hands, with one or more buttons. It sometimes features other

elements, such as "wheels", which allow the user to perform various system-dependent

operations, or extra buttons or features that can add more control or dimensional input.The mouse's motion typically translates into the motion of a cursoron a display, which

allows for fine control of a graphical user interface.

Joy Stick:

Ajoystickis an input device consisting of a stick that pivots on a base and reports its

angle or direction to the device it is controlling. Joysticks are often used to control video

games, and usually have one or more push-buttons whose state can also be read by thecomputer. A popular variation of the joystick used on modern video game consoles is the

analog stick.

The joystick has been the principal flight control in the cockpit of many aircraft,

particularly military fast jets, either as a center stick or side-stick.

Microphones:
http://en.wikipedia.org/wiki/Cursor_(computing)http://en.wikipedia.org/wiki/Computer_displayhttp://en.wikipedia.org/wiki/Graphical_user_interfacehttp://en.wikipedia.org/wiki/Cursor_(computing)http://en.wikipedia.org/wiki/Computer_displayhttp://en.wikipedia.org/wiki/Graphical_user_interface


3/5

Ajoystickis an input device consisting of a stick that pivots on a base and reports itsangle or direction to the device it is controlling. Joysticks, also known as 'control

columns', are the principal control in the cockpit of many civilian and military aircraft,

either as a center stick or side-stick. They often have supplementary switches on them tocontrol other aspects of the aircraft's flight.

Joysticks are often used to control video games, and usually have one or more push-

buttons whose state can also be read by the computer. A popular variation of the joystick

used on modern video game consoles is the analog stick. Joysticks are also used for

controlling machines such as cranes, trucks, underwater unmanned vehicles, wheelchairs,surveillance cameras and zero turning radius lawn mowers. Miniature finger-operated

joysticks have been adopted as input devices for smaller electronic equipment such as

mobile phones.

Output devices:Headphones:
http://en.wikipedia.org/wiki/Cockpithttp://en.wikipedia.org/wiki/Video_game_consoleshttp://en.wikipedia.org/wiki/Analog_stickhttp://en.wikipedia.org/wiki/Mobile_phonehttp://en.wikipedia.org/wiki/Cockpithttp://en.wikipedia.org/wiki/Video_game_consoleshttp://en.wikipedia.org/wiki/Analog_stickhttp://en.wikipedia.org/wiki/Mobile_phone


4/5

Headphones are a pair of small loudspeakers, or less commonly a single speaker, held

close to a user's ears and connected to a signal source such as an audio amplifier, radio,

CD playerorportable media player. They are also known as stereophones, headsets or,colloquially, cans. The in-ear versions are known as earphones orearbuds. In the

context oftelecommunication, the term headset is used to describe a combination of

headphone and microphone used fortwo-way communication, for example with a

telephone.

Printers:

Headphones are a pair of small loudspeakers, or less commonly a single speaker, held

close to a user's ears and connected to a signal source such as an audio amplifier, radio,

CD playerorportable media player. They are also known as stereophones, headsets or,

colloquially, cans. The in-ear versions are known as earphones orearbuds. In thecontext oftelecommunication, the term headset is used to describe a combination of

headphone and microphone used fortwo-way communication, for example with a

telephone.

Scanner:
http://en.wikipedia.org/wiki/Loudspeakerhttp://en.wikipedia.org/wiki/Earhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/CD_playerhttp://en.wikipedia.org/wiki/Portable_media_playerhttp://en.wikipedia.org/wiki/Telecommunicationhttp://en.wikipedia.org/wiki/Microphonehttp://en.wikipedia.org/wiki/Two-way_communicationhttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Loudspeakerhttp://en.wikipedia.org/wiki/Earhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/CD_playerhttp://en.wikipedia.org/wiki/Portable_media_playerhttp://en.wikipedia.org/wiki/Telecommunicationhttp://en.wikipedia.org/wiki/Microphonehttp://en.wikipedia.org/wiki/Two-way_communicationhttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Loudspeakerhttp://en.wikipedia.org/wiki/Earhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/CD_playerhttp://en.wikipedia.org/wiki/Portable_media_playerhttp://en.wikipedia.org/wiki/Telecommunicationhttp://en.wikipedia.org/wiki/Microphonehttp://en.wikipedia.org/wiki/Two-way_communicationhttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Loudspeakerhttp://en.wikipedia.org/wiki/Earhttp://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Radiohttp://en.wikipedia.org/wiki/CD_playerhttp://en.wikipedia.org/wiki/Portable_media_playerhttp://en.wikipedia.org/wiki/Telecommunicationhttp://en.wikipedia.org/wiki/Microphonehttp://en.wikipedia.org/wiki/Two-way_communicationhttp://en.wikipedia.org/wiki/Telephone


5/5

In computing, an image scanneroften abbreviated to just scanner is a device that

optically scans images, printed text, handwriting, or an object, and converts it to a digitalimage. Common examples found in offices are variations of the desktop (or flatbed)

scannerwhere the document is placed on a glass window for scanning.Hand-held

scanners, where the device is moved by hand, have evolved from text scanning "wands"to 3D scanners used for industrial design, reverse engineering, test and measurement,

orthotics, gaming and other applications. Mechanically driven scanners that move the

document are typically used for large-format documents, where a flatbed design would beimpractical.

Monitor:

A monitor ordisplay (sometimes called a visual display unit) is an electronic visual

display forcomputers. The monitor comprises the display device, circuitry, and an

enclosure. The display device in modern monitors is typically a thin film transistor liquidcrystal display (TFT-LCD) thin panel, while older monitors use a cathode ray tube about

as deep as the screen size.
http://en.wikipedia.org/wiki/Handwritinghttp://en.wikipedia.org/wiki/Digital_imagehttp://en.wikipedia.org/wiki/Digital_imagehttp://en.wikipedia.org/wiki/3D_scannerhttp://en.wikipedia.org/wiki/Electronic_visual_displayhttp://en.wikipedia.org/wiki/Electronic_visual_displayhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Electronic_circuithttp://en.wikipedia.org/wiki/Thin_film_transistor_liquid_crystal_displayhttp://en.wikipedia.org/wiki/Thin_film_transistor_liquid_crystal_displayhttp://en.wikipedia.org/wiki/Handwritinghttp://en.wikipedia.org/wiki/Digital_imagehttp://en.wikipedia.org/wiki/Digital_imagehttp://en.wikipedia.org/wiki/3D_scannerhttp://en.wikipedia.org/wiki/Electronic_visual_displayhttp://en.wikipedia.org/wiki/Electronic_visual_displayhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Electronic_circuithttp://en.wikipedia.org/wiki/Thin_film_transistor_liquid_crystal_displayhttp://en.wikipedia.org/wiki/Thin_film_transistor_liquid_crystal_display