The main process behind the water cycle is evaporation, whereby water from the Earth's surface transforms into vapor due to heat from the sun. This vapor rises into the atmosphere, cools, and condenses into droplets, forming clouds through condensation. Eventually, the accumulated moisture falls back to the ground as precipitation, which can be rain, snow, or hail. After precipitation, water may infiltrate the soil, contribute to surface water bodies, or return to the atmosphere through transpiration from plants. This continuous cycle is crucial for maintaining ecosystems and regulating the planet's climate.