George Westinghouse, Jr was an American inventor who lived from 1846 (born October 6) to 1914 (died March 12). He is most famous for starting the Westinghouse Electric Corporation.
Westinghouse senior owned a machine shop, so Jr. had a early understanding of mechanics. He was only 19 when he created his first known invention, the rotary steam engine.
He started out with railroad inventions, such as an air brake, a type of reversible frog (part of the railroad switch), and something to put trains back on the track after they had fallen off. The air brake system was successful enough for him to start a company, The Westinghouse Air Brake Company. This was not his last company, as he went of to form the Union Switch and Signal Company before finally forming the Westinghouse Electric & Manufacturing Company, which eventually evolved into the company we know as Westinghouse.
He helped Tesla by funding the production of his AC motors, in opposition to Thomas Edison. Although Edison, the major power in electrical power at the time favored direct current, Westinghouse and Tesla were able to establish alternating current as the standard. The battle between AC and DC was epic, and you can read more about it in the Nikola Tesla and Thomas Edison nodes.