| mta | Samsung AllShare Metadata |
| mtb | Minitab Exec File |
| mtbl | PIPE-FLO Motor Data Table |
| mtc | BrainVoyager QX Mesh Time Course Data |
| mtdt | Trezor Wallet Metadata |
| mte | Noptel NOS Multi-target Data |
| mtf | SDL Trados Translation Memory Translations |
| mtff | MadgeTech 4 Report Data |
| mtg | Making the Grade Data |
| mtgx | Maltego Graph Data |
| mth | Derive Math File |
| mtkey | proDAD Heroglyph License Data |
| mtm | 3DCS Model MTM Data |
| mtml | Meaningful Text Markup Language Data |
| mtn | PTC Creo Tool Motion Parameter Data |
| mto | FastCAM MTO Data |
| mtp | SpectraMagic NX Template |
| mtst | MotionTracking RAW Image Stack Data |
| mtt | FastCAM MTO Data Template |
| mtt | MetadataTouch Template |
| mttfs | MadgeTech 4 Report Data |
| mtu | Match! User Database |
| mtw | Minitab Worksheet |
| mub | ExtractNow Data |
| muc | Music Collector Collection Data |
| mucow | Adobe Muse Configurable Options Widget |
| mud | Textease Database CT Multi-user Database |
| mudp | Active Safety System Internal Log |
| mulib | Adobe Muse Widget Library |
| mult | SAM Multiple Domain Alignment Output |
| mum | MATLAB Unit Operation Model |
| muphlp | MuPAD Help Data |
| murl | Maxthon Browser URL Data |
| musc | eXtendable Wad Editor MUSC Data |
| musx | Min-U-Script Xpress Data File |