How is the steam engine work today and how did it work in ancient greece

the modern steam engine works like this. A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force is transformed, by a connecting rod and flywheel, into rotational force for work. The anceint greek one worked like this He called it an aeolipile, or "wind ball". His design was a sealed caldron of water was placed over a heat source. As the water boiled, steam rose into the pipes and into the hollow sphere. The steam escaped from two bent outlet tubes on the ball, resulting in rotation of the ball.

which time period is this? or is this story fictional, i'm going to need more info to answer this question