Nicola Tesla (July 10, 1856 - c. January 7, 1943) was a Serbian inventor, physicist, mechanical engineer and electrical engineer. Tesla is recognized among the most accomplished scientists of the late 19th and early 20th centuries. His patents and theoretical work form the basis of modern alternating current electric power (AC) systems, including the polyphase power distribution system and AC motor, with which he helped usher in the Second Industrial Revolution.
Nikola Tesla was born in a Serbian family in Smiljan, Lika, then part of the Austrian Empire, today in the Republic of Croatia. While conducting his work in the United States of America, he became a naturalized U.S. citizen in 1891. The surname "Tesla" is a Slavic word that means adze.
In the United States, Tesla's fame rivaled that of any other inventor or scientist in history or in popular culture. After his demonstration of wireless communication in 1893 and after being the victor in the "War of Currents", he was widely respected as America's greatest electrical engineer. Much of his early work pioneered modern electrical engineering and many of his discoveries were of groundbreaking importance. Never putting a large focus on his finances, Tesla died impoverished and forgotten at the age of 86. In his later years, Tesla was regarded as a mad scientist and became noted for making bizarre claims about possible scientific developments.
Tesla's legacy can be seen across modern civilization wherever electricity is used. Aside from his work on electromagnetism and engineering, Tesla is said to have contributed in varying degrees to the fields of robotics, ballistics, computer science, nuclear physics, and theoretical physics. Tesla considered his exploration of various questions raised by science as ultimately a means to improve the human condition with the principles of science and industrial progress, and one that was compatible with nature. However, many of his achievements have been used, sometimes inappropriately and with some controversy, to support various pseudosciences, UFO theories, and New Age occultism.