Elmer Sperry was an American inventor and entrepreneur who is best known for his pioneering work in the development of navigation, stabilization, and guidance systems for ships, airplanes, and other vehicles. He was also a prolific inventor, holding over 400 patents in his lifetime. He is credited with inventing the gyrocompass, the first practical system for automatically steering ships, and the gyrostabilizer, which enabled aircraft to fly steadily and safely. He also developed the first autopilot system for aircraft.