| .sp3 |
NGS SP3 File |
| .seestyle |
Coda Style Sheet File |
| .sha1 |
SHA-1 Hash File |
| .sgr |
SimCity 4 Graphics Rules File |
| .slogt |
StarLogo Project Template |
| .stats |
FreeSurfer Statistics File |
| .slst |
Game Data File |
| .sdo |
Signed Document |
| .se |
Shuttle Document |
| .sublime-options |
Sublime Text Options File |
| .sublime-settings |
Sublime Text Settings File |
| .sublime-keymap |
Sublime Text Keymap File |
| .sublime-build |
Sublime Text Build File |
| .soundscript |
Rigs of Rods Sound Script File |
| .sass |
Syntactically Awesome StyleSheets File |
| .stskin |
Steam Skin File |
| .sci |
Scilab Script |
| .sxcu |
ShareX Custom Uploader |
| .svh |
SystemVerilog Source Code Header File |
| .server |
MySQL Server Script |
| .sgy |
SEG-Y Data File |
| .spanisher |
Spanisher Word File |
| .sui |
StarSplatter User Interface File |
| .stsg |
SuperTux Saved Game |