What is the difference between an input and output device?

Input and Output exampleAn input device sends information to a computer system for processing, and an output device reproduces or displays the results of that processing. Depending on the interaction, a device can be both; referred to as an input/output or I/O device.

For example, as you can see in the image, a keyboard sends electrical signals (input). Those signals are then interpreted by your computer, and then displayed on a monitor as text (output). Then in the lower half, you can see a computer sending data to a printer that will be reproduced on a piece of paper (output).

More detailed examples

An input device, such as a computer keyboard or mouse, can send information (input) to the computer, but it cannot receive or reproduce information (output) from the computer.

An output device, such as computer speakers or a projector can receive information (output) from the computer, but it cannot send information (input) to the computer.

An input/output device, such as a CD-RW drive or a USB flash drive, can both send information (input) to a computer and receive information (output) from a computer.

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