This category is for listing software for MOD files - either players, or other programs used in song construction or manipulation.
This category is for listing sites explaining the MOD format.
MOD files consist of a combination of sample and pattern data. Each unique sound in a song (for example a bass drum) is stored only once, and repeatedly played.
The term comes from the Amiga program ProTracker, but has since evolved into other formats such as S3M, XM, and IT. All of those files are still called "modules" today.