Distilled water is a water that has virtually all of its impurities removed through distillation. It involves boiling the water and re-condensing the steam into a clean container, leaving contaminants behind. It is used as drinking water in arid seaside areas which do not have sufficient freshwater, by distilling seawater. It is quite common on ships, especially nuclear powered ships, which require a large supply of distilled water as coolant. It is preferable to tap water for use in automotive cooling systems. The minerals and ions typically found in tap water can be corrosive to internal engine components and can cause a more rapid depletion of the anti-corrosion additives found in most antifreeze formulations