MMS files are used by Miles Sound System, a sound software system for for computer games. The library was used to developed hundreds of games for desktop, mobile, or console systems. The first version of API was developed by Johna Milesa in 1991 and is still actively developed.

MMS files store projects created with Miles Sound System. They can contain MIDI, DLS, MLS, MP3, or OGG audio tracks. MMS files are commonly used by software developers.