About General MIDI
GM 1
In September of 1991 the MIDI Manufacturers Association (MMA) and the Japan MIDI Standards Committee (JMSC) created the beginning of a new era in MIDI technology, by adopting the "General MIDI System Level 1" specification (later renamed General MIDI Level 1), also known as "GM" (or now "GM1"). General MIDI 1 was designed to provide a minimum level of performance compatibility among MIDI instruments, and has helped pave the way for MIDI in the growing consumer and multimedia markets.
GM 2
Note: GM2 was updated to version 1.2 in February 2007. Click below to read about the updates.
General MIDI 1 made great strides in the music industry by providing a platform for compatibility between device manufacturers and content providers. Still, many manufacturers felt there needed to be additional functionality. General MIDI 2 is a group of extensions made to General MIDI 1 in 1999, which increases both the number of available sounds and the amount of control available for sound editing and musical performance. All GM2 devices are also fully compatible with General MIDI 1.
GM Lite
The General MIDI Lite device specification, released in 2001, is intended for equipment that does not have the capability to support the full feature set defined in General MIDI 1, on the assumption that the reduced performance may be acceptable (and even required) in some mobile applications. GM Lite represents just one standardized set of performance capabilities for such applications - other performance levels are likely to be standardized in the future.