R2

R2, R02, R.II, R.2 or R-2 may refer to:

Entertainment

 * R2 (Rock'n'Reel), a British music magazine
 * R2-D2, a character from Star Wars films and books, nickname R2
 * Code Geass: Lelouch of the Rebellion R2, a 2008 anime series
 * Resistance 2, a video game
 * Relapse 2, a 2009 album by rapper Eminem
 * Patricio Rey y sus Redonditos de Ricota or R2, an Argentine rock band
 * Region 2, a DVD region code

Science and technology

 * R2 or r2 (pronounced R-square), the coefficient of determination of a linear regression in statistics
 * R2, the two-dimensional real coordinate space in mathematics
 * R2: Risk of explosion by shock, friction, fire or other sources of ignition, a risk phrase in chemistry
 * R2 RNA element, a cis-acting element identified in R2 retrotransposons which is involved in priming the reverse transcription process
 * ATC code R02 Throat preparations, a section of the Anatomical Therapeutic Chemical Classification System
 * Haplogroup R2 (Y-DNA), a human Y-chromosome haplogroup
 * receptor 2, the second in line of a series of cellular receptors, generally at the end of an acronym
 * Gangrene (ICD-10 code)
 * Robonaut 2, a NASA humanoid robotic development project
 * R2 signalling, a family of telephony protocols for line and register signalling

Computing

 * .r02, a RAR file extension
 * Radare2, an open source reverse engineering framework also known as r2

Transportation

 * R2 (Rodalies de Catalunya), a commuter rail line in Barcelona, Catalonia, Spain
 * R2 (RER Vaud), an S-Bahn line in the canton of Vaud


 * Wilmington/Newark Line (R2 Wilmington/Newark line)
 * Warminster Line (R2 Warminster line)
 * Radial Road 2 or R-2, an arterial road of Manila, Philippines
 * Autopista Radial R-2, a Spanish radial motorway connecting Madrid to Guadalajara and passing through Alcobendas and connecting to N-320
 * R2 expressway (Slovakia)
 * R2 Marine Dr, an express bus route in Metro Vancouver, British Columbia, Canada
 * R2 road (Zimbabwe), a road connecting Plumtree and Harare
 * Orenburg Airlines (IATA code)

Vehicles

 * R2, a sub-class of Group R rally cars
 * DFW R.II, a 1918 German bomber aircraft
 * Fiat R.2, a 1919 Italian reconnaissance aircraft
 * HMS Zest (R02), a World War II British Royal Navy Z-class destroyer
 * Jaguar R2, Jaguar Racing's car for the 2001 Formula One season
 * Linke-Hofmann R.II, a World War I German bomber aircraft
 * ORA R2, a Chinese electric city car
 * Panzer 35(t), a Czech tank whose Romanian model was known as the R-2.
 * Polikarpov R-2, a Soviet Union copy of the 1931 British Airco DH.9A light bomber aircraft
 * Ross R-2 Ibis, a glider
 * Subaru R2, a 2003 Japanese car
 * USS R-2 (SS-79), a 1918 R-class coastal and harbor defense submarine of the US Navy

Other uses

 * BBC Radio 2, a British radio station
 * R-2 (missile), an improved version of German V-2 rocket manufactured by the Soviet Union
 * R2 is a rank of United States research university in the Carnegie Classification of Institutions of Higher Education