The Watt steam engine was an early type of steam engine developed by James Watt in the late 18th century. It was the first type of engine to make use of a separate condenser, which greatly improved its efficiency. The engine was used to power a variety of industrial applications, including pumps, mills, and factories. It was also used to power ships and locomotives. The engine was a major breakthrough in the development of the Industrial Revolution and helped to revolutionize manufacturing and transportation.