A fighter plane, or fighter aircraft, is an aircraft designed primarily for attacking other land, air, and sea objects. Fighter planes are the primary means by which armed forces gain air superiority. Fighters are very small, fast, and maneuverable.
The word “fighter” did not become the official British term for a single seat fighter until after World War I. In the RFC/RAF such aircraft continued to be called “scouts”. The French and Germans both used (and still use) terms that literally mean “hunter”. The Americans, perhaps originally due to a mistranslation of the French word “chasseur” called their fighters “pursuit” aircraft until after the Second World War. By whatever name they are known, fighters were developed in response to the fledgling use of aircraft and dirigibles in World War I for reconnaissance and ground attack roles.
As aerial warfare became increasingly important, so did control of the airspace. By World War II, fighters were predominantly all-metal monoplanes with wing-mounted or propeller-mounted cannons. By the end of the war, turbojets were already beginning to replace piston engines as the means of propulsion, and missiles to augment or replace guns.
For historical purposes, jet fighters are classified by generation. The generation terminology was initiated by Russian defense parlance in referring to the F-35 Lightning II as a “fifth-generation” plane. Years are not exact and intended as a guideline.
Modern jet fighters are predominantly powered by one or two turbofan engines, armed primarily with missiles (from as few as two on some lightweight day fighters to as many as eight to ten on air superiority fighters like the Su-27 Flanker or F-15 Eagle), with a cannon as backup armament (typically between 20 and 30mm in calibre), and equipped with a radar as the primary method of target acquisition.