S4, S 4, Š-4, S.4 or S-4 may refer to:

People

* S4 (Dota player), Gustav Magnusson, Swedish ''Dota 2'' player *

S4 (military) A military staff or general staff (also referred to as army staff, navy staff, or air staff within the individual services) is a group of officers, Enlisted rank, enlisted and civilian staff who serve the commanding officer, commander of a D ...

, a logistics officer within military units

Places

County Route S4 (California) There are 34 routes assigned to the "S" zone of the California Route Marker Program, which designates county routes in California. The "S" zone includes county highways in Imperial, Orange, Riverside, San Diego, and Santa Barbara counties. S ...

, a road in San Diego, California

Science and mathematics

Mathematics

S4 algebra In abstract algebra, an interior algebra is a certain type of algebraic structure that encodes the idea of the topological interior of a set. Interior algebras are to topology and the modal logic S4 what Boolean algebras are to set theory and ordi ...

, a variety of modal algebras, also called Interior algebra * Symmetric group S4 (S₄), an abstract mathematical group * S4, a normal modal logic

Chemistry

* S4: Keep away from living quarters, a safety phrase in chemistry *

Tetrasulfur The element sulfur exists as many allotropes. In number of allotropes, sulfur is second only to Allotropes of carbon, carbon.#Greenwood, Greenwood, 652 In addition to the allotropes, each allotrope often exists in Polymorphism (materials science) ...

(S₄), an allotrope of sulfur

Biology

* Fourth heart sound, or S₄, an abnormal heart sound often indicative of congestive heart failure or cor pulmonale * Fourth

sacrum The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1S5) between ages 18 and 30. The sacrum situates at the upper, back part ...

of the vertebral column in human anatomy *

Sacral spinal nerve 4 The sacral spinal nerve 4 (S4) is a spinal nerve of the sacral segment.American Medical Association
...

, a spinal nerve of the sacral segment

Technology

S (programming language) S is a statistical programming language developed primarily by John Chambers and (in earlier versions) Rick Becker and Allan Wilks of Bell Laboratories. The aim of the language, as expressed by John Chambers, is "to turn ideas into software, quic ...

version 4 *

Hibernation Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most ...

a sleeping state in a computer *

SG2 Shareable (Fire Control) Software Suite (S4) The NATO Army Armaments Group (NAAG) Integrated Capability Group Indirect Fires (ICGIF), formerly Land Group 4, and their Sub Group 2 (SG2) on Surface to Surface Ballistics has created a widely used set of shareable fire control software using th ...

Nikon Coolpix S4 The Coolpix S4 is a brand of digital camera produced by Nikon. Its image sensor is a CCD with 6.0 million pixels. It has a thin-film transistor liquid crystal display device with 110,000 pixels. The S4 incorporates Nikon's popular swivel desig ...

, a camera * Samsung Galaxy S4, a smartphone *

Samsung Galaxy S4 Mini The Samsung Galaxy S4 Mini (stylized as Samsung GALAXY S4 mini) is an Android smartphone developed by the Korean manufacturer Samsung Electronics. Announced on May 31, 2013 and released in July 2013, the S4 Mini is a mid-range model of its flags ...

, a mini version of the Samsung Galaxy S4 * Samsung Galaxy Tab S4, an Android tablet

Transportation

Routes

S4 (Berlin) The S4 line number was used by the Berlin S-Bahn between December 1997 and June 2002. The line acted as a temporary route for the re-opened parts of the Berlin S-Bahn ring (''Ringbahn'' in German) until the complete ring was fully re-opened in Ju ...

, an S-Bahn line *

S4 (Munich) Line S4 is a line on the Munich S-Bahn network. It is operated by DB Regio Bayern. It runs from Geltendorf station to Ebersberg station via Pasing, central Munich, Munich East and Grafing station. The line is operated at 20-minute intervals ...

, an S-Bahn line * S4 (Nuremberg), an S-Bahn line * S4 (Rhine-Main S-Bahn), an S-Bahn line * S4 (Rhine-Ruhr S-Bahn), an S-Bahn line *

S4 (St. Gallen S-Bahn) The S4 is a railway service of the St. Gallen S-Bahn that provides hourly service over a circular route (german: Ringzug) that includes , , and , in the canton of St. Gallen. Südostbahn, a private company primarily owned by the federal governme ...

, an S-Bahn line in Switzerland * S4 (RER Vaud), an S-Bahn line in Switzerland * S4 (ZVV) line S4, a line of the S-Bahn Zürich in Switzerland * Bremen S-Bahn line S4 *

Hanover S-Bahn The Hanover S-Bahn (in German: ''S-Bahn Hannover'') is an S-Bahn network operated by DB Regio and Transdev Hannover in the area of Hanover in the German state capital of Lower Saxony. It went operational shortly before Expo 2000 and is focused o ...

line S4 * Rhine-Neckar S-Bahn line S4 * Rostock S-Bahn line S4, a 2010-planned future line * Stadtbahn Karlsruhe line S4 *

Stuttgart S-Bahn The Stuttgart S-Bahn is a suburban railway system (S-Bahn) serving the Stuttgart Region, an urban agglomeration of around 2.7 million people, consisting of the city of Stuttgart and the adjacent districts of Esslingen, Böblingen, Ludwi ...

line S4 * S4, a line of the Brussels Regional Express Network

Vehicles

Alco S-4 The American Locomotive Company (often shortened to ALCO, ALCo or Alco) was an American manufacturer of locomotives, diesel generators, steel, and tanks that operated from 1901 to 1969. The company was formed by the merger of seven smaller locomo ...

, a locomotive *

Audi S4 The Audi S4 is the high performance variant of Audi's compact executive car A4. The original Audi S4, built from 1991 until 1994, was a performance-oriented version of Audi's 100 saloon/sedan. All subsequent S4s since 1997 have been based on ...

, a car *

Lancia Delta S4 The Lancia Delta S4 is a Group B rally car manufactured by the Italian car company Lancia. The Delta S4 competed in the World Rally Championship in 1985 and 1986, until Group B class was disbanded and the cars were eventually banned from competit ...

, a 1984 Group B rally car *

Hydra Technologies Ehécatl The S4 Ehécatl is an unmanned aerial vehicle developed and manufactured by Hydra Technologies of Mexico which, except for its infrared thermal sensor system, is the first of its type to be completely designed and manufactured in Mexico. It is nam ...

, S4, a Mexican unmanned aerial vehicle * Letov Š-4, a 1923 Czechoslovak aircraft * Prussian S 4, an 1894 steam locomotives class * Seibel S-4, a 1951 helicopter *

Supermarine S.4 The Supermarine S.4 was a 1920s British single-engined monoplane built by Supermarine. Designed by a team led by the company's chief designer, R. J. Mitchell, it was built to race in the 1925 Schneider Trophy contest. Mitchell's design ...

, a 1925 British seaplane *

USS S-4 (SS-109) USS ''S-4'' (SS-109) was an S-class submarine of the United States Navy. In 1927, she was sunk by being accidentally rammed by a United States Coast Guard destroyer with the loss of all hands but was raised and restored to service until stric ...

, a 1919 US Navy submarine

Groups, companies, organizations

S04 Fußballclub Gelsenkirchen-Schalke 04 e. V., commonly known as FC Schalke 04 (), Schalke 04 (), or abbreviated as S04 (), is a Professionalism in association football, professional German association football, football and multi-sports club ori ...

, FC Schalke 04, a German professional sports club *

Shift4 Payments Shift4 is an American payment processing company publicly listed on the New York Stock Exchange and based in Allentown, Pennsylvania. The company, founded in 1999 by the then 16-year-old Jared Isaacman, processes payments for over 200,000 busin ...

, a U.S. payment processor *

SATA International SATA (Serial AT Attachment) is a computer bus interface that connects host adapter, host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) ...

(IATA airline designator "S4"), Azores Airlines

Other

S4 (classification) S4, SB3, SM4 are disability swimming classifications used for categorising swimmers based on their level of disability. Swimmers in this class have coordination problems affecting all four of their limbs, or have movement in their arms but no tr ...

, a disability swimming classification *

Form S-4 Form S-4 is a form filed with the U.S. Securities and Exchange Commission The U.S. Securities and Exchange Commission (SEC) is an independent agency of the United States federal government, created in the aftermath of the Wall Street Crash o ...

, a form required by the Securities and Exchange Commission to declare mergers and acquisitions * S4 standard, a set of standards for model railways (

P4 gauge __NOTOC__ Protofour or P4 is a set of standards for model railways allowing construction of models to a scale of 4 mm to 1 foot (1:76.2), the predominant scale of model railways of the British prototype. For historical reasons almost all manuf ...

)