The word is sometimes treated as an adjective, as in "input data," "input signal," "input device," etc. However, adjectives often swap places with the nouns they qualify. Hence you can refer to "data input" to distinguish it from "instruction input." As a verb, it is preferable to say: a computer user "enters" data, which then becomes "input."
Raw data, text, graphics, imagery or commands inserted into a computer.
The process of entering data via a keyboard or terminal or other device.
The material that is entered via a keyboard or terminal.
Pertaining to the device or station where data is sensed or received.