| mcs | The Only Sheet Settings Data |
| mcw | Microsoft Word for Macintosh Document |
| mcx | Mastercam X Document |
| MICRO CADAM-X/6000 Model Data |
| mcx-3 | Mastercam X3 Document |
| mcx-4 | Mastercam X4 Document |
| mcx-5 | Mastercam X5 Document |
| mcx-6 | Mastercam X6 Document |
| mcx-7 | Mastercam X7 Document |
| mcx-8 | Mastercam X8 Document |
| mcx-9 | Mastercam X9 Document |
| mcx2 | Mastercam X Document |
| mcx3 | Mastercam X3 Document |
| mcx4 | Mastercam X4 Document |
| mcx5 | Mastercam X5 Document |
| mcx6 | Mastercam X6 Document |
| mcx7 | Mastercam X7 Document |
| mcx8 | Mastercam X8 Document |
| mcx9 | Mastercam X9 Document |
| md | MarkDown Document |
| Mayura Draw Document |
| MuseData Score |
| md60 | MacDraft 6.0 Document |
| mda | Microsoft Access Add-in |
| mdb | Microsoft Access Database |
| mdbhtml | Microsoft Access Database HTML Document |
| mdd | MacDraft Drawing Document |
| Motion Designer Document |
| mde | Microsoft Access Database |
| mdf | JetForm Design Template |
| mdh | Madhyam Document |
| mdhtml | Microsoft Access Database HTML Document |
| mdk | Madoko Document |
| mdl | Simulink Model |
| mdlp | Simulink Protected Model |
| mdpl | MacDraw II Document |
| mdrw | MacDraw Drawing |
| mdt | Microsoft Access Add-in |
| mdz | Microsoft Access Wizard Template |
| me | Readme Document |
| med | MEDLINE Document |
| medline | MEDLINE Document |
| mell | Mellel Word Processing Document |
| mellel | Mellel Word Processor Document |
| mem | Corel WordPerfect Macro Editor Macro |
| men | MenuPro Menu Document |
| mer | Data Interchange Format |
| met | OmniPage Document |
| metastock | MetaStock Document |
| mez | MusicEase Document |
| mf1 | I-DEAS Model |
| mf2 | I-DEAS Model |
| mfp | Macromedia Flash Paper |
| mga | Manga Document |
| mge | MacGAMUT Mini Demo Data |
| mgmap | MindGenius Mind Map |
| mgmf | MindGenius Map |
| mgmt | MindGenius Template |
| mgmx | MindGenius XML Map |
| mgopml | MindGenius OPML Document |
| mgourmet | MacGourmet Deluxe Document |
| mgourmet3 | MacGourmet Deluxe 3 Document |
| mgourmet4 | MacGourmet Deluxe 4 Document |
| mgp | MagicPoint Presentation File |
| mgs | Equation Illustrator Vector Shapes |
| mgt | Musicnotes Guitar Guru Song |
| mgtpl | MindGenius Template |
| mgtx | MindGenius XML Template |
| mgx | Micrografx Designer Document |
| mht | Multipurpose Internet Mail Extension HTML |
| mhtl | Multipurpose Internet Mail Extension HTML |
| mhtm | Multipurpose Internet Mail Extension HTML |
| mhtml | Multipurpose Internet Mail Extension HTML |
| mhv | Husqvarna Viking MHV Embroidery |
| mhx | MakeHuman eXchange Data |
| mi | CoCreate Document |
| mic | Microsoft Image Composer File |
| mif | Adobe FrameMaker Interchange Format |
| mig | Mighty Draw Drawing |
| min | Cadence OrCAD Min Layout |
