Precipitation processes refer to the various ways in which water vapor in the atmosphere transforms into liquid or solid forms and falls to the Earth's surface. This occurs when air rises, cools, and condenses, forming clouds. When the droplets or ice crystals in these clouds become heavy enough, they fall as rain, snow, sleet, or hail. The main types of precipitation include convectional, frontal, and orographic precipitation. Convectional precipitation happens when warm air rises and cools, while frontal precipitation occurs when warm and cold air masses meet. Orographic precipitation is caused by air rising over mountains, leading to cooling and condensation.