Input and Output Computer Devices

Input and Output Computer Devices Points : Input and Output Computer Devices, Define Input & Output Devices name some input devices & also define each of them, Define “INPUT” and “OUTPUT” devices gives at least four, examples of each device giving their concern with computer. Input devices can enter data into computer in the form of that can be processed by the computer (Binary digits like 0 & 1). Input device translate program and data into a language understandable to the computer. The programmer has an access to computer through this device only. 1. Keyboard This has been the standard input devices for a great number of years a keyboard is an input device that looks like a typewriter based in the QWERTY design. Keyboard divided into five groups.
(i) Alphanumeric keypad.
(ii) Number keypad.
(iii) Functional keypad.
(iv) Screen navigation key or cursor movement keys. i. Alphanumeric keypad This division is the main division of keyboard. This division contains alphabetic keys (a-z), Numeric keys (0-9) and special characters like ! ,@,#,$,%^ etc. ii. Number keypad Numeric keypad located at right side corner. It’s contain ten digits (0-9) nad four arithmetical operators (+, -, *, ./). When num lock is ON. The keys marked as (0-9) and arithmetic operator can be used when num lock OFF. iii. Functional keypad Function keypad located at top side of the keyboard. (Fl ,F2, F3 ………F10 or F12). All of these keys have pre-defined meaning which depend on the software like in ic F2 have RUN command. In Excel F2 have edit command. iv. Screen navigation key or cursor movement keys The blinking cell on the screen called cursor. Cursor control keys arc used to move the cursor around the screen its also contains Pg up, Pg dn , home & end keys. 2. Mouse Mouse is an pointing device. Mouse used for pointing, selecting & executing (clicking) options on the screen. Mouse can use normally in GUI based software. It have two button Right & Left button use for clicking. 3. Track-Ball It is a pointing device, which is use in place of mouse. You use track ball by rolling the ball by figure or palm around the screen. 4. Joystick Joy-stick use for play games its just like a vertical handle which gripped by hand button allows to the user to perform different actions depending on the game. The push button is placed at the base of handle. Is also known as trigger use for firing or hitting. 5. Light Pen Light pen is a light sensitive pen shaped device, that enters command into special screen. Its normally used for drawing , sketching or designing objects engineers &‘ designers use this device frequently. 6. Scanner Its just like photocopier scanner direct entry device that scans or detects images on paper and converts them into computer usable form. Its scans like photograph, sheet diagram form or any thing which on paper diagram form any think which on paper the scanner capable of digitizing not only shape and size drawing but also varying intensities on a gray to black.
> Flatbed scanner
> Hand-held
> Sheet-feed scanner 7. Touch Screen Touch screen just like monitor screen. When we touching figure or any pin type of device on screen. Its capable to allow command to be entered by user’s touching the screen. Touch screen use airports hotels now these days its use in-palm to ATM machine.