Raining is a natural weather phenomenon where water droplets fall from clouds in the atmosphere. This occurs when moisture in the air condenses and becomes heavy enough to overcome air resistance. Rain is essential for replenishing water sources, supporting plant growth, and maintaining ecosystems. Rainfall can vary in intensity, from light drizzles to heavy downpours. It is measured in millimeters or inches and can influence local climates. Different regions experience varying amounts of rain, with some areas, like rainforests, receiving abundant precipitation, while others, like deserts, receive very little.