| mmdb | MaxMind GeoIP2 Database |
| mmdb | Molecular Modeling Database |
| mmdl | Sapphire Structure Model Data |
| mmdr | Adobe Director MMDR Data |
| mme | MIME Encoded Data |
| mmes | Mastersizer 3000 Data |
| mmf | Meal-Master Recipe File |
| mmf | Microsoft Mail Message Format Data |
| mmg | Model Master 3 Axis Flat Data |
| mmi | Media Processing Server Index File |
| mmi | Memory-Map Navigator Place Name Index |
| mmjb | Musicmatch Jukebox Data |
| mmjb_mime | Musicmatch Jukebox MIME Data |
| mmjs | Adobe Dreamweaver Javascript |
| mml | Adobe FrameMaker Document Properties Data |
| mml | Media Catalog MML File |
| mmld | EdGCM MMLD Data |
| mmlic | Mobile Master License Data |
| mmlicinst | Memory-Map Navigator License Data |
| mmm | Adobe Type Manager Multiple-master Font Metrics Data |
| mmm | Music Maker Audio Arrangement Data |
| mmmacro | Mini Mouse Macro Data |
| mmmp | MindManager Map Part |
| mmms | MindManager Map Marker List |
| mmn | Memory-Map Navigator Data |
| mmo | Memory-Map Overlay File |
| mmo | RapidFile Memo Data |
| mmod | MacroModel Molecular Mechanics Data |
| mmp | CoCo Systems VisiMap Data |
| mmp | Metamath Proof Worksheet |
