An input device is any device that provides input to a computer. There are many input devices, but the two most common ones are a keyboard and mouse. Every key you press on the keyboard and every movement or click you make with the mouse sends a specific input signal to the computer.
The keyboard is very much like a standard typewriter keyboard with a few additional keys. The basic QWERTY layout of characters is maintained to make it easy to use the system. The additional keys are included to perform certain special functions. These are known as function keys that vary in number from the keyboard to keyboard.
A device that controls the movement of the cursor or pointer on a display screen. A mouse is a small object you can roll along a hard and flat surface. Its name is derived from its shape, which looks a bit like a mouse. As you move the mouse, the pointer on the display screen moves in the same direction.
A trackball is an input device used to enter motion data into computers or other electronic devices. It serves the same purpose as a mouse but is designed with a moveable ball on the top, which can be rolled in any direction.
A touchpad is a device for pointing (controlling input positioning) on a computer display screen. It is an alternative to the mouse. Originally incorporated in laptop computers, touchpads are also being made for use with desktop computers. A touchpad works by sensing the user’s finger movement and downward pressure.
It allows the user to operate/make selections by simply touching the display screen. A display screen that is sensitive to the touch of a finger or stylus. Widely used on ATM machines, retail point-of-sale terminals, car navigation systems, medical monitors and industrial control panels.
The Light pen is an input device that utilizes a light-sensitive detector to select objects on a display screen.
Magnetic ink character recognition (MICR)
MICR can identify character printed with a special ink that contains particles of magnetic material. This device particularly finds applications in the banking industry.
Optical mark recognition (OMR)
Optical mark recognition also called mark sense reader is a technology where an OMR device senses the presence or absence of a mark, such as a pencil mark. OMR is widely used in tests such as aptitude test.
Bar-code readers are photoelectric scanners that read the bar codes or vertical zebra strips marks, printed on product containers. These devices are generally used in supermarkets, bookshops etc.
A scanner is an input device that can read text or illustration printed on paper and translates the information into a form that the computer can use. A scanner works by digitizing an image.