Who invented the steam locomotive in the 1800s?

The steam locomotive was developed by George Stephenson in the early 1800s. His locomotive, named the "Locomotion No. 1," was built in 1825 and operated on the Stockton and Darlington Railway, the world's first public railway to use steam locomotives. While there were earlier steam-powered vehicles, Stephenson's design significantly advanced locomotive technology and laid the foundation for modern rail transport.