MIDI ( / ˈ m ɪ d i/ Musical Instrument Digital Interface) is a technical standard that describes a communications protocol, digital interface, and electrical connectors that connect a wide variety of electronic musical instruments, computers, and related audio devices for playing, editing, and recording music. This system fits into a single rack case, but before the advent of MIDI, it would have required four separate full-size keyboard instruments, plus outboard mixing and effects units. MIDI logo from the MIDI Manufacturers Association Example of music created in MIDI format Using MIDI, a single controller (often a musical keyboard, as pictured here) can play multiple electronic instruments, which increases the portability and flexibility of stage setups. ( September 2018) ( Learn how and when to remove this template message) Please help improve it to make it understandable to non-experts, without removing the technical details. This article may be too technical for most readers to understand.