(MIDI /mi' -dee/, /mee' -dee/) A hardware specification and protocol used to communicate note and effect information between synthesisers, computers, music keyboards, controllers, and other electronic music devices. IT is basically a high-speed serial connection wITh separate connections for MIDI in, MIDI out and MIDI through (to allow devices to be chained). The basic unIT of information is a "note on/off" event which includes a note number (pITch) and key velocITy (loudness). There are many other message types for events such as pITch bend, patch changes and synthesizer-specific events for loading new patches etc. There is a file format for expressing MIDI data which is like a dump of data sent over a MIDI port. The MIME type "audio/midi" isn' t actually registered so IT should probably be "audio/x-midi". Filenameextension: .mid or .midi . Usenet newsgroups: news:comp.music.midi, news:alt.music.midi. (1998-06-27)