Water in our life plays an important role. It is very essential for all living things like human beings, animals and plants also need water.
Our body contains 70% water by weight. We need to drink about 3 litres of water daily. If we do not drink sufficient water, many functions of our body may stop working. Water is used in digesting food and circulating various nutrients in the body.
Form our body everyday a lot of water passes out as sweat, urine and also water vapors with the air we breathe out. Such water comes out of our body along with wastes and harmful things.
We know that main source of water is rain. The rain water collects in seas, lakes, rivers, streams and ponds. A large amount of rain water goes under the ground and is collected there. We get this water back through the wells and hand-pumps. Even now-a-days, the underground water is received through tube wells too.