S1

S1, S01, S.I, S-1, S.1, Š-1 or S 1 may refer to :

In the military

• S1 (military), an administrative position within military units
• S-1 Loening, a United States Army Air Service seaplane
• S1 Scout Car, an armoured car built in Australia during the Second World War
• S-1 Executive Committee, a United States government entity during World War II responsible for the early stages of the Manhattan atomic bomb project
• USS S-1 (SS-105), a 1918 United States Navy experimental submarine
• Pantsir-S1, a Russian anti-aircraft system
• SSBS S1, a French experimental rocket

Transport

Automobiles

• S1 Scout Car, an armoured car built in Australia during the Second World War
• Invicta S1, a 2004 sport car
• Superformance S1 Roadster, a Lotus Seven Type replicar produced in South Africa between 2001 and 2004, 56 vehicles were produced
• Audi S1, performance variant of Audi A1

Aircraft

• Blackburn Buccaneer S.1 jet naval strike aircraft
• Focke-Wulf S 1, a German Focke-Wulf aircraft
• Fokker S.I, a 1919 Dutch primary trainer aircraft
• Hopfner S-1, a Hopfner aircraft
• Letov Š-1, a 1920 Czechoslovak single-engined, two-seat biplane surveillance aircraft
• Loening S-1, a United States Army Air Service seaplane
• Loughead S-1 Sport 1920 US biplane
• Martinsyde S.1, a 1914 British biplane aircraft
• Pitts S-1 aerobatic biplane
• Swift S-1, a 1991 Polish single seat aerobatic glider

Locomotives

• Alco S-1, a locomotive
• PRR S1, an innovative duplex locomotive developed by the Pennsylvania Railroad
• Prussian S 1, an 1884 steam locomotives class

Lines and roads

• S1 (Berlin), an S-Bahn line
• S1 (Dresden), an S-Bahn line
• S1 (Munich), an S-Bahn line
• S1 (Rhine-Main S-Bahn), an S-Bahn line
• S1 (Rhine-Ruhr S-Bahn), an S-Bahn line
• S1 (Vienna), an S-Bahn line
• S1 National Highway, a National Highways of Pakistan
• Yingbin Expressway, designated S1, an expressway in Shanghai, People's Republic of China
• County Route S1 (California)
• S1 (Long Island bus)
• FGC line S1, a suburban train line in Barcelona Province

In science

Astronomy

• S1, a star orbiting Sagittarius A*, the center of the Milky Way

Biology and Medicine

• S1 (brain region), also known as the Primary somatosensory cortex, the Postcentral gyrus and as Brodmann areas 3, 1 and 2
• Tegafur/gimeracil/oteracil, also known as S-1, a chemotherapy medication

Chemistry

• S1 nuclease, an enzyme that digests singled-stranded DNA and RNA
• S1: Keep locked up, a safety phrase in chemistry

Mathematics

• S¹, the one-dimensional sphere, is a circle.

Measurement

• s⁻¹ (reciprocal seconds, or hertz), a unit of temporal frequency

Businesses

• S1 (Indian television station), a Hindi language television channel
• S1 No. 1 Style, a Japanese adult video company
• S1 Corporation, S1 Corporation

Electronics

• S1 Core, a microprocessor-core
• S1 MP3 Player
• S1 is a transport interface used to connect eNode Bs to EPC in an LTE/4G network.
• ACPI S1 power state in computing
• Apple S1, integrated computer used in the Apple Watch
• Canon PowerShot S1 IS, a 2004 3.2 megapixel digital camera
• FinePix S1 Pro, a 2000 interchangeable lens digital single-lens reflex camera by Fujifilm
• Land Rover S1 by Sonim, a co-branded rugged mobile phone
• Nikon Coolpix S1, a digital camera
• Sendo S1, a Sendo mobile phone model
• Siemens S1, a Siemens mobile phone
• Sony BDP-S1, a first generation Blu-ray Disc (BD) Player
• Samsung_Galaxy_S also commonly called S1 is a smartphone from 2010

Other

• S-1 block cipher, a (hoax) block cipher
• S-1 (Muay Thai), the championship of Muay Thai
• S1 (producer), a hip hop producer, member of the group Strange Fruit Project
• S1 World Championship, an Asian promotions kickboxing organisation
• Bill S-1, a pro forma bill introduced at the beginning of each session of the Canadian Senate
• British NVC community S1, a Carex elata swamp in the British National Vegetation Classification system
• Dungeons & Dragons Module S1: Tomb of Horrors
• Form S-1, an U.S. Securities and Exchange Commission filling used by public companies to register their securities
• Gibson S-1, a guitar made by the Gibson Guitar Corporation
• Schecter S-1, a guitar made by Schecter Guitar Research

Acronyms

a shortening or designation for 

• a postcode covering Sheffield City Centre
• in human anatomy it can refer to either:

• the first sacral vertebra
• the sacral spinal nerve 1 of the vertebral column
• the primary somatosensory cortex in the brain

• Senior 1, the First Year in the Scottish secondary education system
• season one (of a television series)
• the Comet Ikeya-Seki, C/1965 S1
• the Upplands regemente (signal), a 1902 Signal Regiment of the Swedish Armed Forces
• a planned Bremen S-Bahn line
• a Hamburg S-Bahn line
• a Hanover S-Bahn line
• a Nuremberg S-Bahn line
• a RheinNeckar S-Bahn line
• a Rhein-Ruhr S-Bahn line
• a Rhine-Main S-Bahn line
• a Rostock S-Bahn line
• a Stuttgart S-Bahn line
• a Stadtbahn Karlsruhe line
• a star catalogue

With superscripts and subscripts

S₁ may refer to :

• S1 (heart sound), a heart sound in cardiac auscultation

S¹ may refer to :

• S¹, the n-sphere in two dimensions i.e. a circle

S01

S01 may refer to :

• Akai S01, an Akai synthesizer
• ATC code S01 Ophthalmologicals, a subgroup of the Anatomical Therapeutic Chemical Classification System
• HMS Porpoise (S01), a 1956 Porpoise-class submarine of the Royal Navy
• MULTI-S01, an encryption algorithm based on a pseudorandom number generator