| mdq | Database Interface Designer Database Query DaTa |
| mdr | ZX Spectrum Emulator Microdrive Cartridge Data |
| mds | PLINK Multidimensional Scaling Report Data |
| mdsx | MEGA Saved Session |
| mdtext | Markdown Text Data |
| mdtxt | Markdown Text Data |
| mdu | D-Flow FM Model Definition Unstructured Data |
| mdus | MessengerDiscovery Internal Data |
| mdv | SmartWare Modem Definition Data |
| mdw | Microsoft Access Workgroup Data |
| mdx | dBASE IV Multiple Index |
| mdx | MDict Dictionary Data |
| mdy | Sprint RSS iDEN Contact List Data |
| me | Kodak EasyShare Thumbnail Cache |
| mea | Mastersizer 2000 Data |
| mea | Meazure Data |
| meb | Corel WordPerfect ME Bottom Overflow Data |
| meb | PRO100 3D Interior Catalog Element |
| mechdat | ANSYS Mechanical Exported Data |
| mechdb | ANSYS Mechanical Database |
| mecontact | Live Messenger Contacts Data |
| med | Corel WordPerfect Macro Editor Data |
| meg | MEGA Data |
| mega | Megacubo XML Metafile |
| meh | Adobe Acrobat Language Resource Data |
| mem | BPM Studio Sampler Functions Data |
| mem | E-Sword v8 Memory Verses Data |
| mem | Medical Expense Manager Data |
| mem | Medlin Payroll Software Additional Vendor Data |
| mem | Parallels Desktop Memory Dump |
