The hydrologic cycle (water cycle)is a never ending process which has been going on since earth's existence. It contains steps that keep repeating over and over, these are evaporation, condensation, precipitation and runoff. The states that the water goes through are: solid, liquid and gas.
Evaporation, is the first step an invisible process that changes the liquid or ice in a water vapor gas; You may notice this water is not salty as the densest of it is to heavy to rise.The water goes up and makes clouds .Which is also known as condensation, all contains water molecules makes clouds this keeps repeating over into the cloud is to heavy and has to start raining this is called precipitation.
Obviously the cloud is not going to get full and fuller. Eventually it has to start raining in form of water it could be anything from sleet to hail or snow.This water is fresh and safe to drink but where does it all go?
It goes into the last step, runoff. After water has fallen. The water will follow gravity and fall down trees and mountains, to find a larger water source like lakes or oceans;Ground-water is basicly when the water gets infiltrated into the ground and that water is in your tap.
Overall each step is vital in the process and without one of them it would fail.To ensure we have water the process doesnt have a start or finsh and is a never ending cycle meaning there is no new water. Yup thats right we keep reusing the water over and over and no new water has been made for millions of years.