This remarkable Web site contains descriptions and animations of nineteen different kinds of engines. Engine types include internal combustion, steam, and sterling engines, and each page shows how the piston, crankshaft, and other components move together to generate power. The animations demonstrate the processes of intake, compression, and exhaust. Some of the featured engines have more detailed descriptions than others, and oftentimes, a brief account of the engine's history is included. One engine dates back to the early 1700s.