The hydro-logical cycle or the H2O cycle describes the continuous movement of water on, above and below the surface of the earth. It has processes of evaporation, condensation, precipitation, infiltration, runoff and subsurface flow. Also, the water goes through different phases: liquid, solid (ice), and gas (vapor).

The water cycle is the journey of water takes as it circulates from the land to the sky again. The total amount of water on the earth and in its atmosphere does not change but the earths water is always in movement. This circulation and conservation of earths water as it circulates from the land to the sky and back again is called the hydro-logical cycle or water cycle