Nikola Tesla was a Serbian-born American physicist, electrical engineer, and inventor. Tesla was one of the great pioneers of the use of alternating current electricity. Alternating current electricity changes in strength in cycles over time and is the type of electricity that power companies supply to homes today. Tesla invented the alternating current induction generator, a device that changes mechanical energy into alternating current electricity, and the Tesla coil, a transformer that changes the frequency of alternating current.
Nikola Tesla was born on July 9/10 (midnight), 1856 in Smiljam, Croatia, to a Serbian family. His father was an orthodox priest. His mother was unschooled but quite intelligent. Nikola was a dreamer who loved poetry. He was self-disciplined and compulsive. His principle contribution to the field of electromagnetic engineering is the discovery of the rotating magnetic field and the development of the polyphase electrical system. Historians credit Tesla with being a genius because he not only made unique discoveries in electromagnetic engineering but developed these discoveries into working systems in an area of science that had almost no existing body of knowledge other than what he himself had uncovered.
Pioneering experiments were also conducted in fluorescent lighting, vacuum tube, radio, robotics, and X-ray technologies.
As an inventor, he was able to eliminate a lot of models, drawings, and experiments by using the imagination he had developed in childhood to work through the development and trials of a new idea. He would conduct his first experiments in his imaginary world, noting problems and making adjustments, thus completing much of the preliminary work before conducting physical experiments.
The first commercially generated power was direct current. Although alternating current could be more efficiently transmitted, it was not used because no satisfactory alternating current motor had been developed. Tesla pondered this problem for many years.