1. R.U.R. (Rosumovi Umělí Roboti)

2. R6

3. RA (Registration Authority)

4. RAC (Remote Access Concentrator)

5. race hazard

6. rack

7. rack unit

8. rack-mount server

9. RAD (Rapid Application Development)

10. radio button

11. radio link (1)

12. radio link (2)

13. radio modem

14. radio relay

15. radiodetermination

16. radiometry

17. RADIUS (Remote Authentication Dial-In User Service)

18. radix

19. RADSL (Rate Adaptive DSL)

20. RAID (Redundant Array of Independent Disks)

21. RAM (Random-Access Memory)

22. RAMDAC (Random Access Memory Digital-to-Analog Converter)

23. random access

24. RapidIO

25. RAR (Remote Access Router)

26. RARP (Reverse Address Resolution Protocol)

27. RAS (1) (Remote Access Services)

28. RAS (2) (Remote Access Server)

29. RAS (3) (Registration, Admission and Signaling)

30. RAS (4) (Reliability Availability Serviceability)

31. RAS (5) (Row Address Strobe)

32. rasterize

33. Rational Rose

34. raw data

35. ray tracing

36. RC2000 (Radiocom 2000)

37. RC4 (ARCFOUR)

38. RC5 (Ron’s Code 5)

39. RC6 (Ron’s Code 6)

40. RCA connector

41. RCP (Remote Copy Protocol)

42. RCS (Remote Computer Service)

43. RCS (Revision Control System)

44. RDBMS (Relational Database Management System)

45. RDF (Resource Description Format)

46. RDF (Resource Description Framework)

47. RDO (Remote Data Objects)

48. RDP (Remote Desktop Protocol)

49. RDRAM (Rambus DRAM)

50. RDS (Radio Data System)

51. RDS (Remote Data Services)

52. RDSL (Rate-adaptive Digital Subscriber Line)

53. read

54. read access

55. read-only

56. read-only document

57. read-write head

58. real mode

59. real time

60. RealAudio

61. real-time clock

62. real-time processing

63. real-time system

64. reboot

65. receiver

66. reconfigure

67. record (1)

68. record (2)

69. recurring fees

70. recursion

71. recycle bin

72. Red Book

73. Red Hat

74. Red Hat Linux

75. redundancy (1)

76. redundancy (2)

77. referential integrity

78. ReFLEX

79. refresh (1)

80. refresh (2)

81. refresh rate

82. register (1)

83. register (2)

84. registrar

85. registry

86. registry key

87. regular expression

88. relation

89. relational database

90. relative transmission level

91. relay (1)

92. relay (2)

93. release (1)

94. release (2)

95. release notes

96. remote

97. remote access

98. remote computer

99. remote control (1)

100. remote control (2)

101. remote file

102. remote host

103. remote login

104. removable hard disk

105. rendering

106. repeater (1)

107. repeater (2)

108. repeater mode

109. replay

110. replay attack

111. replication

112. report

113. report generator

114. report writer

115. repository (1)

116. repository (2)

117. repudiation

118. request

119. requester

120. resampling

121. reserve account

122. reserved memory

123. reserved word

124. reset

125. reset button

126. residential gateway

127. resize

128. resizing

129. resolution (1)

130. resolution (2)

131. resolution (3)

132. resource (1)

133. resource (2)

134. resource allocation

135. Resource Management Software

136. response (1)

137. response (2)

138. response (3)

139. response time

140. restart

141. return (1)

142. return (2)

143. REXX (Restructured EXtended eXecutor)

144. RF (Radio Frequency)

145. RFC (Request For Comments)

146. RFC 1869

147. RFC 2131

148. RFID (Radio Frequency IDentification)

149. RG58

150. RG8

151. RGB (Red Green Blue)

152. RGBA (Red-Green-Blue-Alpha)

153. RGSS (Rotated Grid Super-Sampling)

154. ribbon cable

155. rich client

156. rich text (1)

157. rich text (2)

158. Rijndael algorithm

159. RIMM (Rambus Inline Memory Module)

160. ring

161. ring network

162. rip

163. RIP (Routing Information Protocol)

164. RIP (Raster Image Processor)

165. RIP (Remote Imaging Protocol)

166. RIPE NCC ( Réseaux IP Européens Network Coordination Centre )

167. ripper

168. RIR (Regional Internet Registry)

169. RISC (Reduced Instruction Set Computer)

170. RISC OS

171. riser card (1)

172. riser card (2)

173. RITL (Radio In The Loop)

174. RJ-11 (Registered Jack - 11) connector

175. RJ-21 (Registered Jack - 21) connector

176. RJ-45 (Registered Jack - 45) connector

177. RJ-48 (Registered Jack - 48) connector

178. RL (Real life (that is, when not chatting))

179. RLE (Run Length Encoding)

180. RLL (Radio Local Loop)

181. RLL (Run Length Limited)

182. RMI (Remote Method Invocation)

183. rn (ReadNews)

184. road-warrior

185. roamer

186. roaming (1)

187. roaming (2)

188. robot (1)

189. robot (2)

190. rogue AP (Access Point) (1)

191. rogue AP (Access Point) (2)

192. rogue site

193. roll back

194. rollover

195. ROM (Read-Only Memory)

196. ROM emulator

197. ROMable

198. root

199. root bridge

200. root directory

201. root domain (1)

202. root domain (2)

203. root server

204. root server system

205. rootkit

206. ROR (Raffing out roud)

207. RosettaNet

208. ROTFL (or ROFL) (Rolling on the floor laughing)

209. ROTFLMAO (Rolling on the floor laughing my a** off)

210. ROTFLMAOWPIMP (Rolling on the floor laughing my a** off while peeing in my pants)

211. ROTFLMBO (Rolling on the floor laughing my butt off)

212. route

213. router

214. routine

215. routing

216. routing control

217. routing table

218. row-level locking

219. RPC (Remote Procedure Call)

220. RPC server

221. RPG (Report Program Generator)

222. RPG (Role-playing games)

223. RPM (Red Hat Package Manager)

224. RPTV (Rear-Projection TeleVision)

225. RS/6000

226. RS-232C (Recommended Standard-232C)

227. RS-422, RS-423

228. RS-449

229. RS-485

230. RS-530

231. RSA (Rivest-Shamir-Adleman)

232. RSAREF

233. RSN (Real soon now)

234. RSS (Radio Service Software)

235. RSS (Really Simple Syndication, RDF Site Summary, Rich Site Summary)

236. RSS (Remote Switching System)

237. RSS (Route Selection Services)

238. RSS feed

239. RSSI (Received Signal Strength Indicator)

240. RSTP (Rapid Spanning Tree Protocol)

241. RSVP (Rapid Serial Visual Presentation)

242. RSVP (Resource Reservation Setup Protocol)

243. RTAM (Remote Terminal Access Method)

244. RTF (Rich Text Format)

245. RTFM (Read the f***ing manual)

246. RTM (Read The Manual)

247. RTOS (Real-Time Operating System)

248. RTP (Rapid Transport Protocol)

249. RTP (Realtime Transport Protocol)

250. RTS (Run-Time System)

251. RTSP (Real Time Streaming Protocol)

252. run (1)

253. run (2)

254. run time

255. runtime engine

256. runtime environment (1)

257. runtime environment (2)

258. run-time error

259. runtime library

260. run-time support

261. run-time, runtime

262. RUP (Rational Unified Process)

263. RxDOS

264. RYO (Roll your own (write your own program; derived from cigarettes rolled yourself with tobacco and paper))