What is .MMM file extension?
File created by Music Maker, a music composition program; contains a multitrack arrangement comprised of music clips, transitions, and effects; can combine multiple imported audio formats into a single music composition.
You can export Music Maker arrangements to several different audio formats, including .WAV, .MP3, .OGG, .WMA, and .MOV.
You can see a list of software programs here on easyfileopener.org that can open this file type so that you don’t need to search for it on the web. You can then open your file with this extension using a software listed below.