Input/output

In computing, input/output (I/O, io, IO, etc.) is the communication between an information processing system (such as a computer) and the outside world, possibly a human or another information processing system.

Inputs are the signals or data received by the system and outputs are the signals or data sent from it.

The term can also be used as part of an action; to "perform I/O" is to perform an input or output operation.

I/O devices are used by a human (or other system) to communicate with a computer.

For instance, a keyboard or mouse is an input device for a computer, while monitors and printers are output devices.

Devices for communication between computers, such as modems and network cards, typically perform both input and output operations.

Duality of input/output relationship

The designation of a device as either input or output depends on perspective.

Mice and keyboards take physical movements that the human user outputs and convert them into input signals that a computer can understand; the output from these devices is the computer's input. Similarly, printers and monitors take signals that a computer outputs as input, and they convert these signals into a representation that human users can understand. From the human user's perspective, the process of reading or seeing these representations is receiving input; this type of interaction between computers and humans is studied in the field of human–computer interaction.

External links

• Input/output @ Wikipedia