| smc | HP Smart Message Center Cache |
| smc | SNES ROM Image SMC |
| smc | Solibri Model Checker Model |
| smc | Soundweb Designer Macro Data |
| smc | Yaskawa YTerm Data |
| smd | Sega Genesis ROM |
| smd | SmartWare II Data |
| smd | Valve Studiomdl Data |
| smdh | Nintendo 3DS Homebrew Application Data |
| smdx | SunSpec Model Definition XML Data |
| sme | SmartEncryptor Encrypted File |
| smf | 3ds Max Character Studio Shared Motion Flow Data |
| smf | Lowrance StructureMap File |
| smf | QSlim 3D Model |
| smf | Serif PagePlus Metafile |
| smf | SkinMagic Toolkit Data |
| smf | SmartCAM Manufacture File |
| smfx | Fusion Pro Temporary Database |
| smg | 3DVIA Composer Model |
| smg | SolidWorks Composer Data |
| smg | USoft System Message Data |
| smggeom | SolidWorks Composer Assembly Geometry Data |
| smgsce | SolidWorks Composer Scenario Definitions Data |
| smgview | SolidWorks Composer View Definitions Data |
| smgxml | SolidWorks Composer Assembly Structure Data |
| smh | Crysfire Data |
| smi | Lotus 1-2-3 Smart Icon |
| smi | SMILES Chemical Document |
| smiles | SMILES Chemical Document |
| smime | OpenSSL S/MIME Format Message |
