On a biological level , water is used to transport materials into and out of our cells. Look back over the background information for air. Our lungs must be wet in order for oxygen to be taken out of the air and into our bloodstream. Water is also used to remove waste from the cells of our body. The importance of water for life is demonstrated by the fact that humans can do without food for several weeks, but we could not survive without water for more than a few days.
Plants have a unique use for water.
So in order for plants to obtain energy, they must have water. On an agricultural level , farming is an enormous consumer of water, and in rain-poor areas water must be pumped in at a huge rate. On a personal level , humans heavily depend on water. We need it to bathe, to wash our clothes, to cook, as well as to drink. On an industrial level , water is used in the manufacture of paper, steel, rubber, chemicals, and other products.