Water is a compound that is essential for all living things and there are everywhere. Water has a chemical compound of hydrogen (H) and oxygen (O) with the chemical formula H2O, meaning a water molecule consists of two hydrogen atoms bonded to one oxygen atom.
In general, there is water in liquid form, but the compound itself has many forms of water such as in the solid form of ice and gas in vapor form. Part of the earth itself is almost 71% of its surface covered by water, where it is most abundant in the oceans as much as 97%, glaciers and Arctic ice cap as much as 2.4% as well as rivers and lakes as much as 0.6%.

Water in the Earth itself rotates continuously through the water cycle including evaporation and condensation or evaporation or cooling (to rain) as well as sublimation or freezing (into ice / snow). Broadly speaking, the process of evaporation from the oceans or through plant respiration contributed to the occurrence of rain or snow on the earth's surface in upland / winter experience.







