Ground water is the water found beneath the surface of the Earth, usually in aquifers. It is a major source of drinking water and is also used for irrigation and other industrial purposes. The term 'ground water' can also be used to refer to the water that is found in the soil. DEW is a form of precipitation that occurs when the air is cooled to its DEW point, causing moisture to condense on surfaces. It is often seen in the early morning hours as droplets of water on grass and other surfaces.