1879 - Thomas Edison does not really “invent” but rather perfects an incandescent light bulb as well as the electrical energy supply system. "We will make electricity so cheap that only the rich will burn candles,” he is reported to say. Edison, one of the most prolific U.S. inventors -- with 1,093 patents to his name -- was also one of the first to apply the principles of mass production and is credited with the creation of the first industrial research laboratory. (National Archives)