Water as the chemical element, can be in three conditions — liquid (water), firm or crystal (an ice, a snow) and gaseous (pairs). Under influence of solar heat water evaporates from a surface of the World ocean and rises in an atmosphere. Here pairs cools down, it is condensed also by rains spills on the ground. The salts containing in sea water, do not evaporate. Therefore to clouds the water which is dropping out on the ground, — too fresh(stale) rises fresh(stale) pairs, and.

Rains pour above a land, especially above heights is more often. Here air is colder, and pairs turns to water, and there, where temperature of air below 0 °С — during a snow more quickly. The Earth absorbs water, accumulating it(her) in underground водоносных layers. The collected water leaves on a surface springs. These sources merge in streams, and streams bear(carry) the waters in the rivers. All the rivers run into the seas and oceans, on a way evaporating water from the surfaces. So the water cycle in the nature owing to which there is a life on our planet is made.