How many (types of) aircraft are there?

Answer

It depends on what criteria you take, for example:

1) all flying machines: with a motor or without a motor

2) without motor: balloons and gliders

3) at the balloons: gas-filled balloons and hot air balloons

4) for the gliders: 3-axis controllable (the classic gliders), the delta gliders, the parachutes and the paragliders

5) in the case of motorized aircraft: the 3-axis (classic aircraft), the motorized deltas, the helicopters, the girocopters, the paramotors, the motorized balloons and zeppelins.

6) for the 3-axle: the single-engine and the multi-engine

7) on the 3-axle: the propeller-driven and the jets. There are even prototypes of “flapping wing” powered aircraft

8) for the 3-axle: the monoplanes, the biplanes and the multi-deckers.

9) in general: seaplanes, (land landing / normal) aircraft, ice landing aircraft.

10) cargo aircraft and passenger aircraft; one-seater aircraft, 2-seaters, etc.

11) and then we forget about rockets, satellites, and so on.