James Watt (January 19, 1736 - August 25, 1819) was a British inventor and an important figure in the first industrial revolution. In 1776, the first practical steam engine was built. Later, after a series of major improvements, it became a "universal prime mover" and was widely used in industry. He opened up a new era of energy utilization for mankind and brought mankind into the "steam age". In order to commemorate this great inventor, later generations set the unit of power as "Watt" (abbreviated as "Watt", symbol W).