Condensation occurs when water vapor, which is the gaseous form of water, is cooled down and turns into liquid water.
In the atmosphere, water vapor is constantly moving and mixing with the air. When warm and moist air rises, it expands and cools down due to the lower pressure at higher altitudes. As the air cools, it becomes less able to hold water vapor, so some of the water molecules start to come together and form tiny water droplets or ice crystals. These droplets or crystals may then combine with other droplets or crystals to form clouds.
Clouds are made up of water droplets or ice crystals that have come together due to condensation. The process of condensation is important in the water cycle, as it leads to the formation of precipitation, such as rain or snow. When the water droplets in clouds become heavy enough, they fall to the ground as precipitation.
Once the precipitation reaches the ground, it may flow across the surface as runoff or seep into the soil to become groundwater. This water may eventually evaporate and re-enter the atmosphere as water vapor, continuing the cycle of condensation and precipitation.