Nikola Tesla was a Serbian American inventor, electrical engineer, mechanical engineer, and futurist best known for his contributions to the design of the modern alternating current (AC) electricity supply system. He was born in 1856 in Croatia and studied engineering at the Graz University of Technology before moving to the United States to work for Thomas Edison. Some of Tesla's greatest inventions included the AC motor and developments in wireless energy transmission. He died in 1943 at the age of 86.