1. RAIT: Redundant Array of Inexpensive Tapes.
  2. RAM: Random Access Memory.
  3. RARP: Reverse Address Resolution Protocol.
  4. RAD: Rapid Application Development.
  5. RADIUS: Remote Authentication Dial In User Service.
  6. RAID: Redundant Array of Independent Disks.
  7. RDBMS: Relation Database Management System.
  8. RDF: Resource Description Framework.
  9. REEAL: Recursive Functions Algorithmic Language.
  10. RF: Radio Frequency.
  11. RGB: Red, Green, Blue (RGBA Red, Green, Blue, Alpha).
  12. RTOS: Real Time Operating System.
  13. RIP: Routing Information Protocol.
  14. ROM: Read Only Memory.
  15. ROMB: Read-Out Motherboard.
  16. ROM-DOS: Read Only Memory-Disk Operating System.