| Abbreviation | Definition |
|---|---|
| RSC | Compiled Resource |
| RSG | EPOC Compiled Resource Header |
| RSL | PC Tools for Windows ReSource Library |
| RSP | Response file |
| RSRC | Resource |
| RSS | EPOC RESource Source File |
| RSS | Really Simple Syndication |
| RT | Rich Text |
| RTF | Rich Text Format - Text document |
| RTFD | NeXT RTF- Packet |
| RTI | Rox Type Information |
| RTL | HP Raster Transfer Language - Bitmap graphics |
| RTL | Run-Time Library |
| RTP | RTPatch Software update file |
| RTPL | Nokia Phone Ring Tone |
| RTS | Computer Associates CA-Realizer Runtime Library |
| RTX | MIME Richtext format Text document |
| RUJ | Run Unit Journal |
| RUL | Echo-Conference Rules file |
| RUN | PC Tools Batch file |