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

Entertainment

* ''

R2 (Rock'n'Reel) ''R2'' is a music magazine published bi-monthly in the United Kingdom. It was launched in 1988 as ''Rock'n'Reel'', changing its name to ''R2'' in early 2009. Content The original ''Rock’n’Reel'' was a pocket-sized fanzine of modest ambitions ...

'', 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 ''Resistance 2'' is a 2008 science fiction Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imaginative and futuristic concepts such as advanced science and technology, ...

'', a video game * ''

Relapse 2 ''Recovery'' (stylized as ''RECOVƎRY'') is the seventh studio album by American rapper Eminem. It was released on June 18, 2010, by Aftermath Entertainment, Shady Records, and Interscope Records. It serves as a direct follow-up to last year’s ...

'', a 2009 album by rapper Eminem *

Patricio Rey y sus Redonditos de Ricota Patricio Rey y sus Redonditos de Ricota, also known simply as Patricio Rey, Los Redondos or Los Redonditos de Ricota, was a rock band formed in La Plata, Argentina. The group was active from the mid 70s up to the early 2000s. They are known for ...

or R2, an Argentine rock band * Region 2, a

DVD region code DVD region codes are a digital rights management technique introduced in 1997. It is designed to allow rights holders to control the international distribution of a DVD release, including its content, release date, and price, all according to ...

Science and technology

* R² or ''r''² (pronounced R-square), the

coefficient of determination In statistics, the coefficient of determination, denoted ''R''2 or ''r''2 and pronounced "R squared", is the proportion of the variation in the dependent variable that is predictable from the independent variable(s). It is a statistic used i ...

of a linear regression in statistics * R², the two-dimensional

real coordinate space In mathematics, the real coordinate space of dimension , denoted ( ) or is the set of the -tuples of real numbers, that is the set of all sequences of real numbers. With component-wise addition and scalar multiplication, it is a real vector ...

in mathematics * R2: Risk of explosion by shock, friction, fire or other sources of ignition, a risk phrase in chemistry *

R2 RNA element R, or r, is the eighteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''ar'' (pronounced ), plural ''ars'', or in Irelan ...

, 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 In biochemistry and pharmacology, receptors are chemical structures, composed of protein, that receive and transduce signals that may be integrated into biological systems. These signals are typically chemical messengers which bind to a recepto ...

, generally at the end of an acronym *

Gangrene Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the ga ...

(ICD-10 code) *

Robonaut 2 A robonaut is a humanoid robot, part of a development project conducted by the Dexterous Robotics Laboratory at NASA's Lyndon B. Johnson Space Center (JSC) in Houston, Texas. Robonaut differs from other current space-faring robots in that, while ...

, a NASA humanoid robotic development project *

R2 signalling Signalling System R2 is a signalling protocol for telecommunications that was in use from the 1960s mostly in Europe, and later also in Latin America, Asia, and Australia, to convey exchange information between two telephone switching systems for es ...

, a family of telephony protocols for line and register signalling

Computing

.r02 RAR is a proprietary archive file format that supports data compression, error correction and file spanning. It was developed in 1993 by Russian software engineer Eugene Roshal and the software is licensed by ''win.rar GmbH''. The name ''RAR' ...

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

Transportation

R2 (Rodalies de Catalunya) The R2 is a line of Rodalies de Catalunya's Barcelona commuter rail service, operated by Renfe Operadora. It is a major north–south axis in the Barcelona metropolitan area, running from the southern limits of the province of Girona to the nort ...

, a commuter rail line in Barcelona, Catalonia, Spain * Wilmington/Newark Line (''R2 Wilmington/Newark line'') * Warminster Line (''R2 Warminster line'') *

Radial Road 2 Radial Road 2 (R-2), informally known as the R-2 Road, is a network of roads and bridges that all together form the second arterial road of Metro Manila in the Philippines. Spanning some , it connects the cities and municipalities of Bacoor, Dasm ...

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 is an expressway ( sk, rýchlostná cesta) in Slovakia, also nicknamed the "southern highway". It starts near Trenčín and ends near Košice. It goes through or around Bánovce nad Bebravou, Prievidza, Žiar nad Hronom, Zvolen, Lučenec, Rima ...

Orenburg Airlines Orenburg Airlines or JSC Orenair (russian: Оренбургские авиалинии) was a Russian airline with its head office on the property of Orenburg Tsentralny Airport in Orenburg. It operated domestic passenger services and inclusive t ...

(IATA code)

Vehicles

* R2, a sub-class of Group R rally cars * DFW R.II, a 1918 German bomber aircraft *

Fiat R.2 The Fiat R.2 was a reconnaissance aircraft produced in Italy shortly after World War I, and the first aircraft to be marketed under the Fiat brand, (previous Fiat aircraft had been marketed as by SIA). It was a conventional two-bay biplane with e ...

, a 1919 Italian reconnaissance aircraft * HMS ''Zest'' (R02), a World War II British Royal Navy Z-class destroyer *

Jaguar R2 The Jaguar R2 was the car with which the Jaguar team competed in the Formula One season. It was driven by Eddie Irvine, who was in his second year with the team, and Luciano Burti, who had deputised for Irvine at the 2000 Austrian Grand Prix. ...

, Jaguar Racing's car for the 2001 Formula One season *

Linke-Hofmann R.II The Linke-Hofmann R.II (''Riesenflugzeug'' – "giant aircraft") was a bomber aircraft designed and built in Germany from 1917. Design and development The Linke-Hofmann R.I had disappointing performance and handling, as well as structural we ...

, 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 The Airco DH.9A was a British single-engined light bomber designed and first used shortly before the end of the First World War. It was a development of the unsuccessful Airco DH.9 bomber, featuring a strengthened structure and, crucially, repla ...

, 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 BBC Radio 2 is a British national radio station owned and operated by the BBC. It is the most popular station in the United Kingdom with over 15 million weekly listeners. Since launching in 1967, the station broadcasts a wide range of content. ...

, 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 A research university or a research-intensive university is a university that is committed to research as a central part of its mission. They are the most important sites at which knowledge production occurs, along with "intergenerational kno ...

in the