The Supermarine Spitfire is a British single-seat fighter aircraft used by the Royal Air Force and many other Allied countries throughout the Second World War. The Spitfire continued to be used into the 1950s both as a front line fighter and in secondary roles. It was produced in greater numbers than any other British aircraft and was the only Allied fighter in production throughout the war. After the Battle of Britain, the Spitfire became the backbone of RAF Fighter Command and saw action in the European, Mediterranean, Pacific and the South-East Asian theatres. Much loved by its pilots, the Spitfire served in several roles, including interceptor, photo-reconnaissance, fighter-bomber, carrier-based fighter, and training.