A set of messages that allows a tape unit, or anything that behaves like a tape unit (such as a hard disk recording system, or DAW software) to be controlled via MIDI. The messages include the typical commands such as one might find on a professional tape unit: stop, play, record, rewind, etc. A set of more advanced commands allows for jog/shuttle and locate functions. The messages are a subset of the Universal Real-Time sysex messages. Unfortunately, MMC has not been widely adopted; some devices which would benefit from it use Continuous Controller messages instead.