Born in Serbia to Croatian parents, he studied electrical engineering in Austria. After leaving school he took up work on the first telephone company in Hungary, later transferring his life to Paris to work for the Edison company. In Paris, he developed the idea for an induction motor, one of the most important applications of alternating current to the problem of power generation.
Tesla came to the United States in 1884 to work for Thomas Edison. Though he contributed to solving many of Edison's problems in electrical generation, the two clashed over wages and, more importantly, whether AC or DC was a better source of power. Tesla eventually left the Edison company and worked for himself, when he joined Westinghouse. There he developed hundreds of innovations and received many patents for the crucial parts of our present electrical system, including polyphase motors and electrical transmission systems. He and Westinghouse demonstrated the usefulness of AC power when they used it to illuminate the 1893 World's Fair in Chicago.
Tesla made more accomplishments than I can possibly list and describe here, but among them are the first proof of radio communication, which antedated Marconi's demonstration, and a functioning spark plug. Among his other areas of theoretical research were the wireless transmission of power, a directed electric force weapon, and ionic flying machines.
Margaret Cheney, Tesla: Man Out of Time
Mark Seifer, Wizard: The Life and Times of Nikola Tesla
Nikola Tesla (and David Hatcher Childress), Fantastic Inventions of Nikola Tesla