| .rtf |
Rich Text Format File |
| .rpt |
Generic Report |
| .rtd |
Robot Structural Analysis Design File |
| .rtfd |
Rich Text Format Directory File |
| .readme |
Readme File |
| .rzk |
Red Zion Key File |
| .rst |
reStructuredText File |
| .rzn |
Red Zion Notes File |
| .ris |
Research Information Systems Citation File |
| .run |
Linux Executable File |
| .rad |
Radar ViewPoint Radar Data |
| .rvf |
RichView Format File |
| .rtx |
Rich Text Document |
| .rft |
Revisable Form Text Document |
| .sig |
Signature File |
| .scm |
StarCraft Map File |
| .saf |
Street Atlas USA Map File |
| .save |
Nano Temporary Save File |
| .sct |
Windows Scriptlet |
| .smf |
StarMath Formula File |
| .sxw |
StarOffice Writer Document |
| .sdw |
MrSID World File |
| .safetext |
SafeText File |
| .strings |
Text Strings File |