F4, F.IV, F04, F 4, F.4 or F-4 may refer to:

Aircraft

* Flanders F.4, a 1910s British experimental military two-seat monoplane aircraft * Martinsyde F.4 Buzzard, a British World War I fighter version of the Martinsyde Buzzard biplane *

Fokker F.IV The Fokker F.IV was an airliner designed in the Netherlands in the early 1920s, with only two ever made, both for the United States Army Air Service (designated T-2). Design and development The Fokker F.IV was constructed in typical Fokker st ...

, a 1921 Dutch airliner *

Caproni Vizzola F.4 The Caproni Vizzola F.4 was an Italian fighter aircraft prototype that was designed in 1937 and built from 1939. It was a single-seat, low-wing cantilever monoplane with retractable landing gear. Development The F.4 was developed in parallel wit ...

, an Italian prototype fighter of 1939 * Lockheed F-4 Lightning, a reconnaissance variant of the Lockheed P-38 Lightning World War 2 fighter *

Fleetwings Sea Bird The Fleetwings Sea Bird (or Seabird) was an American-built amphibious aircraft of the 1930s. Design and production The Sea Bird was an amphibious utility aircraft designed in 1934–1935 by James C. Reddig for Fleetwings, Inc., of Bristol, Penn ...

, a variant of which was the F-4 * A number of aircraft that first entered service with the U.S. Navy: ** Curtiss F4C, a 1920s version of the Naval Aircraft Factory TS biplane fighter ** Boeing F4B, a 1930s version of the

Boeing P-12 The Boeing P-12/F4B was an American pursuit aircraft that was operated by the United States Army Air Corps , United States Marine Corps, and United States Navy. Design and development Developed as a private venture to replace the Boeing F2B a ...

biplane fighter **

Grumman F4F Wildcat The Grumman F4F Wildcat is an American carrier-based fighter aircraft that entered service in 1940 with the United States Navy, and the British Royal Navy where it was initially known as the Martlet. First used by the British in the North Atlant ...

, a carrier-based fighter aircraft in World War 2 **

Vought F4U Corsair The Vought F4U Corsair is an American fighter aircraft which saw service primarily in World War II and the Korean War. Designed and initially manufactured by Chance Vought, the Corsair was soon in great demand; additional production contract ...

, a World War 2 fighter **

Douglas F4D Skyray The Douglas F4D Skyray (later redesignated F-6 Skyray) is an American carrier-based fighter/ interceptor built by the Douglas Aircraft Company. Although it was in service for a relatively short time (1956–1964) and never entered combat, it w ...

, a carrier-based fighter/interceptor, first flight 1951 **

McDonnell Douglas F-4 Phantom II The McDonnell Douglas F-4 Phantom II is an American tandem two-seat, twin-engine, all-weather, long-range supersonic jet interceptor and fighter-bomber originally developed by McDonnell Aircraft for the United States Navy.Swanborough and B ...

, a supersonic fighter-bomber, first flight 1958

Art, entertainment, and music

* F4, or Flower 4, the four handsome boys appearing in Japanese manga '' Boys Over Flowers'' *

F4 (band) F4 (Flower Four) or JVKV was a Taiwanese boy band consisting of Jerry Yan, Vanness Wu, Ken Chu, and Vic Chou. The group F4 was formed in 2001 after the Taiwanese drama '' Meteor Garden'' that they starred in was widely successful. Together th ...

, Taiwanese boy band * ''

F4 Thailand ''F4 Thailand: Boys Over Flowers'' ( th, F4 Thailand : หัวใจรักสี่ดวงดาว BOYS OVER FLOWERS; ) is a Thai television series starring Tu Tontawan Tantivejakul (Tu), Vachirawit Chivaaree (Bright), Jirawat Sutivanich ...

'', a Thai television series * F₄, Middle

F (musical note) F is a musical note, the fourth above C or fifth below C. It is the fourth note and the sixth semitone of the solfège. It is also known as fa in fixed-do solfège. It has enharmonic equivalents of E (E-sharp) and G (G-double flat), amongst ...

* Fantastic Four, fictional superhero team

Computing and technology

* Faugère's F4 algorithm in computer algebra * F4, a

function key A function key is a key on a computer or terminal keyboard that can be programmed so as to cause an operating system command interpreter or application program to perform certain actions, a form of soft key. On some keyboards/computers, function ...

on a computer keyboard * f4transkript, a transcription software

Mathematics

* F₄ (mathematics), the name of a Lie group and also its Lie algebra f₄ * ''F₄'',

Fermat number In mathematics, a Fermat number, named after Pierre de Fermat, who first studied them, is a positive integer of the form :F_ = 2^ + 1, where ''n'' is a non-negative integer. The first few Fermat numbers are: : 3, 5, 17, 257, 65537, 42949672 ...

Sports and games

F4 (classification) F4, also T4 and SP4, is a wheelchair sport classification that corresponds to the neurological level T1- T7. Historically, it was known as 1C Incomplete, 2 Complete, or Upper 3 Complete. People in this class have normal upper limb function, and ...

, a wheelchair sport classification *

Formula 4 FIA Formula 4, also called FIA F4, is an open-wheel racing car category intended for junior drivers. There is no global championship, but rather individual nations or regions can host their own championships in compliance with a universal set of r ...

, a class of car racing * ''f4'', designates a square in

Algebraic notation (chess) Algebraic notation (or AN) is the standard method for recording and describing the moves in a game of chess. It is based on a system of coordinates to uniquely identify each square on the chessboard. It is used by most books, magazines, and new ...

* 1. f4, or Bird's opening, an opening move in chess

Transportation and vehicles

F4 (Istanbul Metro) The F4, officially referred to as the F4 Boğaziçi Üni./Hisarüstü–Aşiyan funicular line ( tr, F4 Boğaziçi Üni./Hisarüstü–Aşiyan füniküler hattı) is a long funicular railway in Beşiktaş, Istanbul. When opened on 28 October 2022 ...

, a funicular railway in Istanbul Turkey *

F4 Cross Harbour The Cross Harbour ferry service, officially known as F4 Cross Harbour, was a commuter ferry service in Sydney, New South Wales. Part of the Sydney Ferries network, it was operated by Transdev Sydney Ferries and serviced the Darling Harbour, ...

, or Cross Harbour ferry services, Sydney, Australia *

Albarka Air Albarka Air was an airline based in Abuja, Nigeria. It operated scheduled and charter services within Nigeria and charters to other countries in central and west Africa. Its main base was Nnamdi Azikiwe International Airport, Abuja.Flight Interna ...

(IATA code), a Nigerian airline *

Front-engine, four-wheel-drive layout In automotive design, an F4, or front-engine, four-wheel drive (4WD) layout places the internal combustion engine at the front of the vehicle and drives all four roadwheels. This layout is typically chosen for better control on many surfaces, ...

, in automotive design *

MV Agusta F4 series The MV Agusta F4 is an inline four-cylinder sport bike made by MV Agusta from 1999 until 2018. It was the motorcycle that launched the resurrection of the brand in 1998. The F4 was created by motorcycle designer Massimo Tamburini at CRC (Cagiva ...

, a series of motorcycles * Saginaw Airport (FAA identifier F04), a defunct public airport in Fort Worth, Texas, U.S. * USS ''F-4'', a U.S. Navy submarine that sank near Honolulu harbor in 1915

Other uses

* F4, a

paper size Paper size standards govern the size of sheets of paper used as writing paper, stationery, cards, and for some printed documents. The ISO 216 standard, which includes the commonly used A4 size, is the international standard for paper size. I ...

* F 4 Frösön, a former Swedish Air Force wing * ''f/4'', an

f-number In optics, the f-number of an optical system such as a camera lens is the ratio of the system's focal length to the diameter of the entrance pupil ("clear aperture").Smith, Warren ''Modern Optical Engineering'', 4th Ed., 2007 McGraw-Hill Pro ...

of an optical system such as a camera lens * F-4 Object, or Rákosi bunker, a formerly secret nuclear shelter in Budapest, Hungary *

Form F-4 Form F-4 is an American Form used to register securities in connection with business combinations and exchange offers involving foreign private issuers. These activities include mergers & acquisitions, going-private transactions, rights offerings ...

, an American form used to register securities *

Nikon F4 The Nikon F4 is a 35 mm autofocus (AF) single lens reflex (SLR) film camera, introduced in 1988 as the next generation in Nikon's line of F series professional cameras. With industrial design by Giorgetto Giugiaro, the F4 was the first pro ...

, a camera * F4, a tornado intensity rating on the

Fujita scale The Fujita scale (F-Scale; ), or Fujita–Pearson scale (FPP scale), is a scale for rating tornado intensity, based primarily on the damage tornadoes inflict on human-built structures and vegetation. The official Fujita scale category is deter ...

* F4, an electrode site according to the

10–20 system (EEG) The 10–20 system or International 10–20 system is an internationally recognized method to describe and apply the location of scalp electrodes in the context of an EEG exam, polysomnograph sleep study, or voluntary lab research. This metho ...