What are steam engines?

A steam engine is like a powerful friend who helps move big things by using hot water vapor.

Imagine you have a kettle on the stove. When it boils, steam comes out of the spout, that’s hot vapor pushing its way out. A steam engine uses this same idea but on a much bigger scale.

Inside a steam engine, there's a big tank where water is heated until it becomes steam. This steam pushes against a piston, like when you blow up a balloon and it moves forward. The piston goes back and forth, turning a wheel that can make trains move or lift heavy objects.

Before steam engines, people used horses to pull carts or push things around. But with a steam engine, you could go faster and carry more, just like how a toy car moves when you press the button instead of pushing it by hand.