C1

C1, C01, C.I or C-1 may refer to:

Diverse

• C1, an international standard paper size defined in ISO 216 (648×917 mm)
• Bills C-1 and S-1, a pro forma bill normally introduced at the start of a parliamentary session in the Canadian House of Commons
• C1, also known as Vlakplaas, a unit of the South African Police responsible for assassinating opponents of Apartheid during the 1980s
• $C^1$, in mathematics, refers to the set of all continuously differentiable functions
• C1, a note-octave in music
• C1, a level in the Common European Framework of Reference for Languages
• C1, the use class for hotels, in town and country planning in the United Kingdom
• C1, the first of four pure modules taken in the Advanced Level (UK) Maths syllabus
• C1, a NRS social grade in the United Kingdom for the lower middle class
• a 2001 1.3 megapixels Olympus digital camera model
• a Yamaha grand piano model
• a class of FM radio broadcasting in North America
• C1 pylon, a type of high voltage pylon
• C1 Television, a Mongolian Television Channel
• Schecter C-1 Hellraiser FR, a guitar model
• Caldwell 1 (NGC 188), an open cluster in Cepheus
• Cluster 1, also known as Rumba, an ESA satellite

Biology

• C1 domain, an important secondary messenger protein domain
• C1-inhibitor, a human serine protease inhibitor
• C1 regulatory sequence for the insulin gene
• Apolipoprotein C1, a human lipoprotein
• Chlorophyll c1, a form of chlorophyll
• Cytochrome C1, a precursor protein to Cytochrome C
• Proanthocyanidin C1, a type of polyphenolic compound
• Prostaglandin C1, a form of prostaglandins
• C1 & P1 (Neuroscience), a component of the visual evoked potential
• ATC code C01, a subgroup of the Anatomical Therapeutic Chemical Classification System
• C01, the ICD-10 code for "malignant neoplasm of base of tongue", a form of Oral cancer

Human anatomy

• Cervical vertebra 1, the first cervical vertebrae of the vertebral column
• Cervical spinal nerve 1, a spinal nerve of the cervical segment

Computing

• C0 and C1 control codes defined in ISO 6429
• C1 (protocol), a 1984 protocol for file transfer, also known as "Punter"
• C-One, a single-board microcomputer
• Counter-Strike "C1", a slang expression from the video game, used to express agreement
• TCSEC C1 security class
• C1 NES TV, a family of Nintendo-television-set hybrids manufactured by Sharp Corporation in 1983
• ATI C1, codename of the Xbox 360 GPU Xenos
• a CPU power state in the Advanced Configuration and Power Interface

Transport, vehicles, ships or public transport routes

• C-1 Trader, a cargo-version of the S-2 Tracker anti-submarine warfare aircraft of the United States Navy
• AEG C.I, a German World War I reconnaissance aircraft
• AGO C.I, a 1915 German reconnaissance biplane
• Albatros C.I, a 1915 German two-seat general-purpose biplane
• Aviatik C.I, a 1915 German observation plane
• Bavarian C I, a 1847 German steam locomotives class
• BMW C1, a security scooter with a roof
• Chevrolet Corvette C1, any model corvette sold from 1953 to 1962, denoted a solid-axle rearend
• Cierva C.1, a 1920 Spanish experimental autogyro
• Circumferential Road 1, a highway in the Philippines
• Citroën C1, a small car
• DFW C.I, a WWI German reconnaissance aircraft
• Douglas C-1, a cargo/transport airplane produced by Douglas Aircraft for the U.S. Army Air Service starting in 1925
• Fokker C.I, a 1918 German reconnaissance biplane
• Ford C1 platform, the Ford Motor Company's global compact car automobile platform
• Friedrichshafen C.I, a 1914 German single-engined amphibious reconnaissance biplane
• GNR Class C1, a British 4-4-2 steam locomotive
• Hansa-Brandenburg C.I, a 1916 German 2-seater armed single-engine reconnaissance biplane
• HMS C1, a C-class submarine of the Royal Navy
• Kawasaki C-1, an indigenous transport aircraft of the Japanese Air Self-Defense Forces
• LB&SCR C1 class, a 1882 British freight steam locomotive
• London Buses route C1
• NER Class C1, a British 0-6-0 steam locomotive
• Nimrod NRA/C1, a 1981 test design racing car
• PRR C1, an American PRR steam locomotive
• Route C1 (Shuto Expressway), the Inner Loop of Tokyo's Shuto Expressway system.
• Rumpler C.I, a 1915 German two-seater single-engine reconnaissance biplane
• Sauber C1, a Sauber sport car
• Type C1 ship, a small cargo vessel built by the United States in large numbers before and during World War II
• USS C-1 (SS-9), a C-class submarine of the United States Navy
• USS Newark (C-1), a protected cruiser of the United States Navy
• Claro M. Recto Avenue, a road in Metro Manila, Philippines
• Southern Cross Airport (FAA LID: C01)
• C-1, the numberplate of the Prime Minister of Australia's official VIP transportation
• The One-way traffic sign from the Vienna Convention on Road Signs and Signals
• Type of heavy goods vehicle licence, allowing its holder to drive vehicles (other than buses) with maximum GVWR of 7,500 kg (16,535 lb.) and to pull a trailer with a maximum GTWR of 750 kg

Sports

• C1, an abbreviation for single-person canoe
• C1, an abbreviation for Class One offshore powerboat racing
• 'C1', the top category in Group C sportscar racing, used between 1985 and 1990
• C1, the UEFA Champions League (formerly known as the European Cup) in football
  • Serie C1, the third highest football league in Italy until 2008

See also

• 1C (disambiguation)