George Westinghouse, Jr (October 6, 1846–March 12, 1914) was an American entrepreneur and engineer who invented the railway air brake and was a pioneer of the electrical industry. Westinghouse was one of Thomas Edison's main rivals in the early implementation of the American electricity system. Westinghouse's system using alternating current ultimately prevailed over Edison's insistence on direct current. In 1911, he received the AIEE's Edison Medal 'For meritorious achievement in connection with the development of the alternating current system light.

Westinghouse was the son of a machine shop owner and was talented at machinery and business. He was only 19 years old when he created his first invention, the rotary steam engine. At age 21 he invented a "car replacer", a device to guide derailed railroad cars back onto the tracks, and a reversible frog, a device used with a railroad switch to guide trains onto one of two tracks.

Thomas Edison was one of his main rivals due to the fact that they were both very intelligent inventors. At about this time he witnessed a train wreck where two engineers saw one another, but were unable to stop their trains in time using the existing brakes. Brakemen ran from car to car, on catwalks atop the cars, applying the brakes manually on each car.