| roo | Oracle CODASYL DBMS Database Root |
| root | HippoDraw ROOT Ntuples |
| rop | PSS/E OPF Model |
| ror | Resources of a Resource File |
| rot | STK Central Body Rotation File |
| rou | Route 66 Route Data |
| rou | EnRoute v3 Toolpath Data |
| rov | Siebel Report Object Variable |
| rox | Siebel Report Object Executable |
| roz | aSc Timetables Data |
| rp2 | RetroPlatform Player Archive |
| rp9-snapshot | RetroPlatform Snapshot Image |
| rpb | Radmin Phonebook |
| rpc | BillQuick Enterprise Invoice Data |
| rpc | Crystal Reports RPC File |
| rpc3 | NI Diadem RPC3 File |
| rpcp | Reason Resource Data |
| rpd | Oracle BI EE Repository |
| rpe | Performance Analyzer Data |
| rpf | CARE-S InfoWorks Runoff Parameters Data |
| rpk | RadLight Media Player Skin |
| rpk | Rail Simulator Package |
| rpn | Act! v2 Report Data |
| rpr | ArchiCAD Roof Properties |
| rpres | RStudio R Presentation |
| rpt | Crystal Reports Report |
| rpt | BI/Query Report Specification |
| rptdesign | Actuate BiRT Report Design |
| rptlibrary | Actuate BiRT Report Library |
| rpv | RealPlayer Visualization |
