“Hydro” means “water” in Greek so as the name indicates the electric energy that is generated or produced using the energy or force in the water is called hydroelectric energy. Water has a gravitational force when it is falling of flowing so that energy is used to generate electricity.
The most widely used form of energy is this hydroelectricity. It is a form of renewable energy, whose cost of production is low when compared to other energy forms. This is also a flexible form because ramping up and down can be done very fast to meet out the demands.
The use of water energy dates back to the ancient times as they have used this to grind flour and have performed many other tasks.