Nikola Tesla was a Serbian-born inventor who lived from 1856 to 1943. His most famous contribution to the world was the first alternating current generator, invented in 1882. He is also noted for inventing the Tesla coil, and a bladeless turbine that functioned on fluid viscosity.
Though he had worked for Thomas Edison for a time, he would soon become his adversary due to Edison's promotion of direct current for power distribution (Alternating current is now generally considered superior for this purpose). At the time, direct current was the standard and Edison was not about to lose all his patent royalties to a former employee. A huge political battle ensued, including the use of Tesla's patents (by one of Edison's employees) to construct the first electric chair for the state of New York in order to promote the idea that alternating currents were deadly. But with the financial backing of George Westinghouse, Tesla's alternating current gradually replaced direct current, enormously extending the range and improving the safety and efficiency of power distribution.
Of the 700-plus patents accumulated by Tesla, the most controversial today is his Wardenclyffe Tower. Though never completed successfully in Tesla's lifetime due to lack of funding, and finally dismantled for scrap during wartime, its principles are being implemented by a U.S. military project in Alaska, spanning several hundred acres. However Project HAARP, as it is called, supplies a different objective. While Tesla's WardenClyffe Tower was to be his supreme test of the applicability of transmitted power, HAARP is used to study ionospheric effects on radio communication.
Tesla's Serbian-Orthodox family and the Yugoslav embassy struggled with American authorities after Tesla's death due to the potential power of some of Tesla's research. He studied in Karlovac, Croatia, and worked in Budapest, Paris and New York City. He was fluent in seven languages and was a good friend of Mark Twain.
Perhaps because of Tesla's personal eccentricity and the dramatic nature of his demonstrations, conspiracy theories about applications of his work persist. The common Hollywood stereotype of "mad scientist" closely mirrors Tesla's real-life persona, or at least a charicature of it, which may be no accident considering that many of the earliest such movies (including the first movie version of Mary Shelley's Frankenstein) were produced by Edison.