Audio file used by Electronic Arts games for the PlayStation 2 (PS2), PlayStation 3 (PS3), and PC; saves audio data for the game soundtrack and used for playing background music; often used by the Need For Speed series games.

Examples of Need for Speed games that use MUS files include Need for Speed: Most Wanted (NFS: MW), Need for Speed: Underground (NFSU), and Need for Speed: Carbon (NFSC). For the PC, NFS: MW stores MUS files in the \SOUND\PFDATA\ game installation directory. NOTE: The NFSMW Music Extractor program can convert MUS files from NFSMW into many different .WAV files.

Music notation format used by Finale and other MakeMusic notation programs; saves data in MIDI format, similar to a .MID file; also contains additional information that can only be read by MakeMusic software.

MUS files contain music notation information, but do not store actual audio data. NOTE: After the release of Finale 2014, the program began to use .MUSX files instead of MUS files.

Audio file used by Minecraft, a 3D open-ended sandbox construction game; saves background music played during the game; may also store music played by in-game Music Discs (i.e., virtual CDs).

MUS files may be plain audio stored in the Ogg Vorbis (.OGG) format, or they may use encryption that cannot be read by standard audio players. A Java tool called muscode.jar can be used to convert Minecraft MUS files to the OGG format.