How many types of airplanes are there?

Airplanes vary greatly in the size, structure, engines, and purpose. That is hard to describe without further clarification of the question. But I think this is the answer you are looking for. Airship/Balloon - aircraft that is lighter than air. Glider/Sailplane - aircraft that has no engine. It flys using the energy of the air or launched by an external propulsion. Powered airplanes - various sub-types

-Human-powered airplane

-Solar-powered airplane

-Nuclear-powered airplane

-Propeller driven airplane

-Jet-powered airplane

-Rocket-powered airplane Helicopter/Rotorcraft - Main rotor provides lift and propulsion Autogyro/Gyroplane - main(top) rotor provides lift only. Requires another method of thrust to push it forwar, such as another propellor. Fixed Wing Bi-planes - I like to consider the old airplanes, such as the Wright Brothers, as a unique aircraft. They were built of wood covered with fabric and very fragile. But they are very much like modern airplanes in the way they fly. This points out how Aircraft can be categorized by how they are constructed. Fixed Wing Monoplanes - Most of today's commercial air transport aircraft are fixed wing monoplanes. 'Fixed wing' means that the wing does not move (in its entirety) and 'monoplane' means one set of wings. So the list can be endless.