| skn | Symbian OS Skin Data |
| skn | Windows Automotive Skin |
| skp | COREX Orthographic Transcription with Signal Linking Data |
| skp | Sage Accounting Print Data |
| skp | SSEYO Koan Play Data |
| skpkmz | SketchUp Data |
| skr | Gaussian Scratch File |
| skr | PGP Private Keyring File |
| skr | ScriptIt Data |
| sks | Show.kit Template |
| skt | SSEYO Koan Design |
| skt | SSEYO Koan Play Data |
| sku | TomTom for R-Link Map Update |
| sky | Adobe Acrobat Language Resource |
| skypechatstyle | Skype Chat Style Data |
| skypeemoticonset | Skype Emoticon Pack |
| sl | RenderMan Shader Source |
| sl | Sam Spade Startup Script |
| sl2 | Lowrance Sonar Log v2 File |
| sl2 | SQLite 2.0 Database |
| sl3 | SQLite 3 Database |
| slb | Multiframe Sections Library |
| slb | PSpice Symbols Library |
| slbk | Smart Launcher Home Screen Backup |
| slc | SLiCe Format Data |
| sld | Corel Paint Shop Pro Styled Line Data |
| sld | NEPLAN Graphic Export Data |
| sld | XnView Slideshow |
| sldasm | SolidWorks Assembly Document |
| sldblk | SolidWorks Blocks File |
| sldbombt | SolidWorks BOM Template |
| sldclr | SolidWorks Color Palette Data |
| sldd | Simulink Data Dictionary |
| slddc | Simulink Data Dictionary Cache |
| sldedb | SolidWorks Database |
