MIDI is associated with the storage of music files. MIDI is an acronym for

MIDI expands to Musical Instrument Digital Interface, a standard that lets electronic instruments, computers and software exchange performance data.

A MIDI file stores instructions such as which note, how long and how loud rather than recorded sound itself.

The other three expansions are invented labels that do not match the recognised MIDI standard.

Because MIDI carries note data, the same file can be played back with different instrument sounds.

This keeps MIDI files far smaller than audio recordings like WAV or MP3.

MIDI was introduced in 1983 to let synthesizers from different makers work together.