The idea of an aeroplane has been around for centuries, and Sir George Cayley figured out the best way of making things fly (through aerodynamic)
Working gliders had been built in the 1850s by Sir George Cayley, but the first self-powered aircraft was created by Wikipedia:John Stringfellow, an Englishman who created a model aircraft that had its first successful flight in 1848.
Clément Ader constructed and designed a self-powered aircraft. On October 9, 1890, Ader attempted to fly the Éole, which succeeded in taking off and flying uncontrolled a distance of approximately 50 meters before witnesses
The first real aircraft test was that of the Wright brothers on 17th December 1903 which is recognised as "the first sustained and controlled heavier-than-air powered flight."