A model airplane is a small sized Unmanned Aerial Vehicle. It may be a replica of an existing airplane or an imaginary aircraft.
Model aircraft are generally divided into two basic types, flying and non-flying. Non-flying models are also called static, display, or shelf models. Flying models range from simple toy gliders to powered scale models. Some can be very large, especially when used to simulate the conditions of a real flight. Static models range from mass produced toys to highly accurate models used for museum display.
Aircraft manufacturers and researchers use wind tunnel models. They are used for testing new designs and development of new ones. Sometimes only part of the aircraft is modeled.