| rbl | RegexBuddy Library Data |
| rbm | Tekla Structures Reinforcement Mesh Properties |
| rbr | libigl ReAntTweakBar Data |
| rbt | Xilinx Raw BIT Data |
| rbtx | Lego Mindstorms NXT Create Pack and Go File |
| rc1 | Samsung S5230 Firmware RSRC1 File |
| rc2 | Samsung S5230 Firmware RSRC2 File |
| rca | RCA Anaesthetic Logbook Document |
| rcb | Ripple Chat Bot Data |
| rcd | Symantec pcAnywhere Recorded Session |
| rcg | Recog Character Recognition Set |
| rch | SWAT Reach Output Data |
| rci | SPEFO Rectified Cleaned Data |
| rcj | Robocopy Job Data |
| rck | REScheck Data |
| rcn | QRacing Track Records Data |
| rcq | RESTClient Requests File |
| rcr | SAP Business One XL Reporter Data |
| rctd | RabbitCT Dataset |
| rcut | Webinaria Recording Cut |
| rcw | RaceSail Regatta Data File |
| rd | Reaction Data File |
| rd1 | DATAIR Retirement Plan Document System Data |
| rd3x | Reflection Desktop Session Data |
| rd5x | Reflection Desktop Session Data |
| rda | Oracle Database Storage Area |
| rda | Siemens MR Spectroscopy ASCII Data |
| rdat | RNA Data |
| rdb | Oracle Database Root |
| rdc | CYANA Residual Dipolar Coupling Restraint File |
| rdd | IBM Informix Genero Studio Data Schema |
| rdf | Reaction Data File |
| rdh | Siemens MR Spectroscopy Header Data |
| rdi | SPEFO Differential Spectrum Data |
| rdml | Real-time PCR Data Markup Language Data |
