| .SSV | Seavus | Fichiers de jeu | Seavus Secure Project File | Seavus Project Viewer | Seavus |
| .ST3 | National Instruments | Fichiers de jeu | SPICE Status Data | Spice | National Instruments |
| .STA | Dassault Systèmes | Fichiers de jeu | ABAQUS Status File | ABAQUS software suite | Dassault Systèmes |
| .STG | Microsoft Corporation | Fichiers de jeu | ActiveSync Backup File | Microsoft ActiveSync | Microsoft Corporation |
| .STL | 3D Systems | Fichiers de jeu | Stereolithography File | Creo Parametric 3D Modeling Software | PTC |
| .STN | ON1, Inc. | Fichiers de jeu | Genuine Fractals Image | Adobe Photoshop | Adobe Systems Incorporated |
| .STO | Ecru Software | Fichiers de jeu | PRO100 3D Interior Design Project | Ecru Software PRO100 | Ecru Software |
| .STP | Unknown Developer | Fichiers de jeu | STEP 3D CAD File | CATIA | Dassault Systèmes |
| .STR | dBase, LLC | Fichiers de jeu | dBASE Structure List Object File | dBase | dBase, LLC |
| .STS | DuoS DSEMU | Fichiers de jeu | DuoS DSEMU Saved State File | DuoS DSEMU | Unknown Developer |
| .STUFF | CCP Games | Fichiers de jeu | EVE Online Data File | EVE Online | CCP Games |
| .SUB | URUWORKS | Fichiers de jeu | Subtitle File | CyberLink PowerDVD | CyberLink |
| .SUD | Aivosto Oy | Fichiers de jeu | Super Project Analyzer Data File | Super Project Analyzer | Aivosto Oy |
| .SV | Playsoft | Fichiers de jeu | Roland Garros Tennis File | Roland Garros Tennis Champions | Playsoft |
| .SV1 | Atari Corporation | Fichiers de jeu | RollerCoaster Tycoon Saved Game File | RollerCoaster Tycoon | Chris Sawyer |
| .SV4 | Chris Sawyer | Fichiers de jeu | RollerCoaster Tycoon Saved Game | RollerCoaster Tycoon | Chris Sawyer |
| .SV5 | Atari Corporation | Fichiers de jeu | Chris Sawyer's Locomotion Saved Game File | RollerCoaster Tycoon | Chris Sawyer |
| .SV6 | Chris Sawyer | Fichiers de jeu | RollerCoaster Tycoon 2 Saved Game | RollerCoaster Tycoon 2: Triple Thrill Pack | Chris Sawyer |
| .SV7 | Nintendo | Fichiers de jeu | Saved Game File | No Cash GBA (No$GBA) | Martin Korth |
| .SV8 | Atari Corporation | Fichiers de jeu | RollerCoaster Tycoon Game Data | RollerCoaster Tycoon | Chris Sawyer |
| .SVE | Simutrans Development Team | Fichiers de jeu | Simutrans Saved Game | Simutrans | Simutrans Development Team |
| .SVG | Nintendo | Fichiers de jeu | Saved Game File | No Cash GBA (No$GBA) | Martin Korth |
| .SVH | IEEE Xplore | Fichiers de jeu | SystemVerilog Source Code Header File | Microsoft Notepad | Microsoft Corporation |
| .SVS | Nintendo | Fichiers de jeu | Game Boy Advance Saved State File | Game Boy Advance | Nintendo |
| .SVT | Runic Games | Fichiers de jeu | Torchlight Saved Game File | TorchTools | Open Source |
| .SWC | Adobe Systems Incorporated | Fichiers de jeu | Flex Components Archive | Adobe Animate CC 2017 | Adobe Systems Incorporated |
| .SWE | Electronic Arts | Fichiers de jeu | NHL Ice Hockey 2002 Required Data | NHL 2002 | Electronic Arts |
| .SWV | Microsoft Corporation | Fichiers de jeu | Microsoft Sidewinder Game Voice Settings File | SideWinder Game Voice Utility | Microsoft Corporation |
| .SWW | Ubisoft | Fichiers de jeu | Anno Saved Game | ANNO 2070 | Ubisoft Blue Byte |
| .SXT | FMJ-Software | Fichiers de jeu | Propellerheads Reason 2 NN-XT Sound Data | FMJ-Software Awave Audio | FMJ-Software |
| .SYB | Microïds | Fichiers de jeu | Syberia II Game Archive File | Syberia II | Microïds |
| .SYN | Image-Line | Fichiers de jeu | SimSynth Document | FL Studio 12 | Image-Line |
| .SYSTEM | Open Source | Fichiers de jeu | Vega Strike Virtual System File | Microsoft Notepad | Microsoft Corporation |
| .SZS | Nintendo | Fichiers de jeu | Wii Game Data File | Wiimms SZS Toolset | Nintendo |
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