"It is raining" refers to the phenomenon where water droplets fall from the atmosphere to the ground. This occurs when clouds become saturated with moisture, leading to precipitation. Rain is an essential part of the Earth's water cycle, helping to replenish rivers, lakes, and groundwater. Rain can vary in intensity, from light drizzles to heavy downpours. It plays a crucial role in supporting ecosystems, providing necessary hydration for plants and animals. Additionally, rain can impact human activities, influencing agriculture, transportation, and outdoor events. Weather forecasts often predict rain to help people prepare for wet conditions.