Water circulation refers to the continuous movement of water within the Earth's systems, primarily through processes like evaporation, condensation, and precipitation. This cycle begins when the sun heats water in rivers, lakes, and oceans, causing it to evaporate into the atmosphere. Once in the atmosphere, water vapor cools and condenses to form clouds. Eventually, the water falls back to the Earth as precipitation, such as rain or snow, replenishing water sources and supporting ecosystems. This process is essential for maintaining the balance of ecosystems, climate, and water resources on our planet.