Everyone knows that water is a very important natural resource. It is actually possible for one to stay for a month without food however it is most difficult to spend a week without water. Water constitutes 70% of our brains and 60% of one's body mass. It only makes 3% of the earth's surface, but in that 3 there's 1% that is available for human use. Taking note of these facts tells one just how critical this useful resource is.