A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a biplane wing structure has a structural advantage over a monoplane, it produces more drag than a monoplane wing. Improved structural techniques, better materials and higher speeds made the biplane configuration obsolete for most purposes by the late 1930s.
First World War Sopwith Camel biplane
1920s biplane hang glider
The Gloster Gladiator, a World War II fighter biplane
Soviet Antonov An-2 biplane from the 1940s
A fixed-wing aircraft is a heavier-than-air flying machine, such as an airplane, which is capable of flight using aerodynamic lift. Fixed-wing aircraft are distinct from rotary-wing aircraft, and ornithopters. The wings of a fixed-wing aircraft are not necessarily rigid; kites, hang gliders, variable-sweep wing aircraft, and airplanes that use wing morphing are all classified as fixed-wing aircraft.
A Boeing 737 airliner is an example of a fixed-wing aircraft
The fixed wings of a delta-shaped kite are not rigid
Children flying a kite in 1828 Bavaria, by Johann Michael Voltz
Le Bris and his glider, Albatros II, photographed by Nadar, 1868