| real | Gnome Desktop Data |
| reality | RealityKit 3D Scene |
| reals | ScadaWorks Real Bank Template |
| reapeaks | REAPER Media Peak Information |
| reapindex | REAPER Media Peak Index |
| rec | Easy CD Creator Recovery Data |
| rec | Epidata Data File |
| rec | Medlin Payroll Software Bank Reconciliation Data |
| rec | Recogniform ICR Data File |
| rec | Windows 3.1 Macro Recorder Data |
| rech | 4D Database for Mac Search Document |
| red | CARE-S InfoWorks Rainfall Data |
| red | IBM Rational Rose Module Diagram |
| redif | ReDIF Template |
| redis | Redis Database |
| ref | Ad-Aware Signature Data |
| ref | PLINK Long-format Reference Allele File |
| ref | RFSCAT Simulator Wind Field Reference Data |
| ref | WinPLOTR Refined Parameters Data |
| reference | Budget In Brief Reference Data |
| refx | E-Sword Reference Library Note Data |
| reg-auto | WOW! Diagnostic Registration Data |
| regkey | Zoom Player Registration Key Data |
| regs | Netscape Navigator Registry Data |
| regularizer | SAM Transition Regularizer Data |
| rek | Fraunhofer EZRT Volume Data |
| rel | 3DCS Simulation Related List Data |
| rel | my Knowledge Relation Data |
| rel | PLINK Text Relationship Matrix |
| remotecodec | Reason Remote Codec Data |
| remotemap | Reason Remote Mapping Data |
| renderman | RenderMan Data |
| renv | Rhino 3D Saved Environment Data |
| rep | Act! Report Data |
| repx | XtraReports Report Definition |
