Any form of water that falls from the clouds is known as precipitation. There are several forms of precipitation including rain, snow, hail and sleet. Depending on the geographic region and climatic conditions, any of these forms of precipitation may take place. Generally, rainfall is the more common form of precipitation.
Precipitation is one of the chief processes comprising the hydrologic (or water) cycle. The total amount of water on Earth is fixed; it simply rotates through various processes, forming the water cycle. The water that is precipitated reaches the surface of Earth and ultimately makes it to surface or ground water bodies. The evaporation of water takes place from surface water bodies and the condensation of this water results in the formation of clouds. From there, the precipitation brings this water back to Earth's surface, thus completing the entire water cycle.
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