Natural water usually contains a number of microscopic contaminants, along with dissolved minerals such as calcium and iron. To remove these elements from water is to boil it until it changes to steam, a process known as distillation. When this steam is allowed to cool down and condense into liquid form again, the result is a purified form called distilled water. Distilled Water is used in chemical and biological laboratories, as well as industry. Distilled water is also commonly used tofill the lead acid batteries used in cars and trucks