This document summarizes the history and development of helicopters from Leonardo Da Vinci's early sketches in 1480 to the first practical helicopter in 1933. It describes key developments such as Forlanini using steam power in 1800 and Cornu's piloted flight in 1907. The document also explains the basic flying principles of helicopters, including how main and tail rotors provide lift and control directional movement, allowing helicopters to hover and fly in any direction.