Many centuries ago, the ancient Romans used a vast network of aqueducts to bring water to the city from outlying regions.

Early Europeans and Asians used water wheels placed in flowing streams to turn big stone wheels that ground up grains for making bread. They were called grist mills.

More recently, dams were implemented to impede the flow of running water and release it when needed. The force of the water then turns generators to make electricity for modern society.