The steam may be used to power an engine by spinning a turbine or by pushing pistons.
Huge turbines drive electric generators and giant ships.
Piston steam engines power large pile drivers. In some countries, locomotives with piston steam engines are still used to pull railroad trains. In the United States, diesel locomotives pull most trains. The development of the steam engine in the 1700's made modern industry possible. Until then, people had to depend on the power of their own muscles or on animal, wind, and water power.