We call our planet earth, but say that we should call it water. Water covers more than 70 percent of our planet. Water is essential to life on earth. We drink it, swim in it, clean with it, and use it in many other ways. Surprisingly , the amount of water on earth does not decrease even though we use so much of it every day. This is nature recycles water in a process called the water cycle (also called the hydrologic cycle). The water cycle is the movement of water from earth into atmosphere and back to earth again.