Input Devices

An input device is any hardware used to feed data and instructions into the computer. It converts the information a human provides — letters, numbers, clicks, sounds, images — into the electronic form the computer can understand and process. Input devices form the input unit of the computer.

Common input devices:

1. Keyboard. The most common input device, used to type letters, numbers, symbols, and commands. A standard keyboard has typing keys, number keys, function keys (F1–F12), and special control keys.
2. Mouse. A pointing device that moves a pointer on the screen and lets the user select, click, drag, and open items. It usually has left and right buttons and a scroll wheel.
3. Scanner. A device that reads a printed page, photograph, or document and converts it into a digital image that can be stored and edited in the computer.
4. Microphone. Takes in sound (voice or music) and converts it into digital form for recording, voice commands, or online calls.
5. Webcam / digital camera. Captures still pictures or live video and sends it into the computer.
6. Joystick. A stick-like control device used mainly to play games and to move objects on the screen.
7. Light pen / touch screen. A touch screen acts as both an input and an output device — you see the display (output) and touch it to give commands (input); it is very common on smartphones and tablets.
8. Barcode reader. Reads the striped barcode printed on products (as used at shop billing counters) and feeds the product code into the computer — a device commerc students meet often in retail and inventory systems. …