Water cycle: Water present in water bodies including sea, oceans, rivers and lakes evaporates due to sun's heat. Water is further released in large amounts by the leaves of plants.
The water vapour rises up, cools down and condenses to form tiny droplets of water. These droplets unite to form clouds. This process keeps on repeating and water drops in the clouds fall on earth as rain. Sometimes, if temperature is very low, rainwater falls as hail or snow.