Input Devices

Keyboard – It is like a typewriter keyboard with 101 keys arranged in 5 groups as

Alphanumeric – A-Z, 0-9 plus some more characters.

Modifier – Shift, Ctrl (control key), Alt (alternate key).

Function – The function keys (F1, F2….F12) to give the special commands.

Cursor movement – Arrow keys to the position of cursor on the screen.

Special purpose– Used for specific function like esc, print screen, scroll lock & pause.

Mouse – A pointing device used to position the pointer, to create graphics, for click and drag-and-drop. Ball or optical mouse is connected by PS/2 port or USB port to computer.

Scanners – It converts printed image to electronic by shining light and sensing the intensity of the reflection. It is of various types like

Bar code reader – It is used for reading bar codes on products.

Optical Character Recognition (OCR) – It translate image to text by OCR software.

Optical Mark Reader (OMR) – It recognize marks by pencil or pen and used in answer sheets.

Magnetic Ink Character Recognition (MICR) – It is used in banks to process cheques.

Touch Screens, Voice Recognition Devices are also some other input devices.