Editing C2

{{Self reference|For the Wikipedia C2 criterion for speedy deletion, see {{slink|Wikipedia:Criteria for speedy deletion#C2}}.}}
{{Wiktionary}}
'''C2''' or a derivative ('''C-2''', '''C<sup>2</sup>''', etc.) may refer to:
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==Mathematics and physics==
* ''C''<sub>2</sub>, one of the common notations for the [[cyclic group]] of order 2
* ''C''<sup>2</sup> [[differentiability class]]
* ''C''<sup>2</sup> or <math>\Complex^2</math>, the [[complex coordinate plane]]
* ''c''<sup>2</sup> the square of the [[speed of light]] (in the mass–energy equivalence formula)

==Biology==
* [[C2 domain]], a protein structural domain
* [[C2 regulatory sequence]] for the insulin gene
* [[Apolipoprotein C2]], a human apolipoprotein
* In human anatomy, C2 may refer to:
** [[Cervical vertebra 2]], the axis, one of the cervical vertebrae of the vertebral column
** [[Cervical spinal nerve 2]]
* [[Chlorophyll c2]], a form of chlorophyll
* [[Complement component 2]]
* [[Procyanidin C2]], a plant phenolic compound
* [[Prodelphinidin C2]], a plant phenolic compound
* [[Vitamin C2 (disambiguation)]]
* the ATC code for ''[[Antihypertensives]]'', a subgroup of the Anatomical Therapeutic Chemical Classification System
*C<sub>2</sub> fragments, one of the types of products of [[catabolism]] pathways
* [[Haplogroup C-M217]], also known as C2, a [[Human Y-chromosome DNA haplogroup]]

==Chemistry==
* C<sub>2</sub>, [[Diatomic carbon]], a molecule made of two carbon atoms
* C2=, [[ethylene]], a two carbon alkene

==Codes or abbreviations==
'''C2''' may be a code or abbreviation for:
* [[C2 Aquarii|C<sup>2</sup> Aquarii]], a star
* [[C2 Centauri|C<sup>2</sup> Centauri]], a star
* [[C2 (Code Geass)]], an anime character
* [[C2 explosive]], a form of plastic explosive
* [[C2 pylon]], a type of high voltage pylon
* [[C2 radio class]], a class in FM broadcasting in America
* [[C2 (classification)]], a para-cycling classification
* [[Group C2]], the secondary class of Group C sports car racing
* [[BRDC C2 Championship]], a short lived sports car racing series which ran from 1988 to 1990
* [[Nimrod NRA/C2]], a 1982 Group C racing car
* C2, an international standard paper size defined in [[ISO 216]] (458×648&nbsp;mm)
* C2, a level in the [[Common European Framework of Reference for Languages]]
* C2, the [[NRS social grade]] between C1 and D
* C2s, substances listed in [[Controlled Substances Act#Schedule II controlled substances|Schedule II of the Controlled Substances Act]] in the United States
* [[Command and control]], the exercise of authority by a commanding officer over military forces in the accomplishment of a mission
* [[Air Luxor]] IATA airline code
* [[C2 Pictures]], a film company related to Carolco Pictures
* [[Bill C-2]], various legislation of the Parliament of Canada
* C2, or C<sub>2</sub> a note-octave in music, aka [[Low C]]

==Computing==

* C2, a computer security class, defined in the [[Trusted Computer System Evaluation Criteria]]
* C2, a bytecode compiler that is part of the [[HotSpot (virtual machine)|HotSpot]] virtual machine implementation
* [[C2 (protocol)]], a 1985 Commodore file transfer protocol
* [[C2 error]], a read error of a compact disc
* [[C2.com]] or WikiWikiWeb, the first user-editable website
* [[Cryptomeria cipher]], a cipher used in digital rights management
* [[Botnet#Command_and_control|Command and control (malware)]]
* [[Codec 2]], speech compression codec.

==Transportation and space==
* [[C2 class Melbourne tram]]
* [[Bavarian C II (Ostbahn)]], an 1862 German steam locomotive
* [[Bavarian C II.1]], an 1857 German steam locomotive
* [[Bavarian C II.2]], an 1861 German steam locomotive
* [[Chevrolet Corvette (C2)]], the generation of the Chevrolet Corvette produced between 1962 and 1967
* [[Citroën C2]], a car produced by Citroën in 2004
* [[Cluster II (spacecraft)]], an ESA space mission
* [[Ford C2 platform]], an automobile platform produced by Ford since 2018
* [[GNR Class C2]], a British 4-4-2 steam locomotive class
* [[LNER Class C2]], classified C1 during GNR ownership 
* [[Kawasaki C2]], a bike
* [[London Buses route C2]]
* [[LB&SCR C2 class]], an 1893 British 0-6-0 steam locomotive
* [[Circumferential Road 2]] or C-2, an arterial road of Manila, Philippines
* [[Saf-T-Liner C2]], a school bus built by Thomas Built Buses
* [[Saturn C-2]], a 1960 conceptual American launch vehicle
* [[Type C2 ship]], a type of all-purpose cargo ship
* [[C2 (yacht)]], a luxury motor yacht
* [[Central Circular Route (Shuto Expressway)]] in Tokyo, Japan
* [[Mei-Nikan Expressway]], route C2 in Nagoya, Japan

==Military and aviation==
* [[Command and control]], the exercise of authority and direction by a commanding officer
* [[C-2 (poison)]], developed in the ''Poison laboratory of the Soviet secret services''
* [[C2A1]], Squad Automatic Weapon variant of the FN FAL formerly in Canadian Service
* [[ACAZ C.2]], a Belgian prototype fighter aircraft of the 1920s
* [[AEG C.II]], a German World War II armed reconnaissance aircraft
* [[Aeronca C-2]], an American airplane
* [[AGO C.II]], a German reconnaissance biplane of World War I
* [[Cierva C.2]], a 1921 Spanish experimental autogyro 
* [[DFW C.II]], a World War I German reconnaissance aircraft 
* [[Fokker C-2]], the American military version of the Fokker F.VII aircraft
* [[C-2 Greyhound]], the Grumman cargo aircraft of the United States Navy
* {{HMS|C2}}, a British C class submarine of the Royal Navy
* [[Kawasaki C-2]], a military transport aircraft
* [[LFG Roland C.II]], a 1915 advanced German reconnaissance aircraft
* [[LVG C.II]], a 1910s German two-seat reconnaissance biplane 
* {{USS|C-2|SS-13}}, a C-class submarine of the United States Navy
* {{USS|Charleston|C-2}}, a protected cruiser of the United States Navy

==Other==
* C2, [[UEFA Cup Winners' Cup]] in football, later merged with UEFA Cup (now [[UEFA Europa League]])
* [[C2 Pictures]], a film studio
* [[C-2 visa]], a nonimmigrant visa which allows individuals to travel to and from the headquarters of the United Nations
* [[Coca-Cola C2]], a soft drink launched by The Coca-Cola Company in 2004
* ''[[Conduit 2]]'', a 2011 first-person shooter video game
* [[AEW Continental Classic]], a professional wrestling tournament

==See also==
* [[CO2]]
* [[CII (disambiguation)]]
* [[2C (disambiguation)]]

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