.S3M File Extension
File TypeScreamTracker 3 Module
What is an S3M file?
Audio module format used by Scream Tracker 3.0 and later; contains sound samples and music patterns, which define what notes are played back by the samples; similar to a .MOD file, but allows up to 16 tracks.
Scream Tracker v.1 and 2 saved songs as .STM files. The newer S3M format is more versatile and more widely supported. All three versions were originally developed by Future Crew.