Leonardo da Vinci's wing-flapping flying-machine designs are known as ornithopters.
An ornithopter is an aircraft intended to fly by flapping wings, imitating the motion of birds or insects. The word comes from Greek roots meaning bird and wing. Leonardo made numerous studies of bird flight and designed mechanisms in which a pilot would move wing structures through pedals, levers, or other linkages.
His ornithopters were sketches and theoretical machines rather than completed aircraft. Human muscles cannot provide enough sustained power for a large bird-like machine using the materials available to Leonardo, so these designs were not practical airplanes.
Leonardo also investigated gliding and screw-based flight. That variety matters because he did not develop one single aircraft prototype; he explored several possible ways to generate lift. Modern ornithopters exist as small experimental aircraft and toys, but they do not turn Leonardo's Renaissance designs into successful human-carrying machines.