Distilled water is water that has been purified through the process of distillation, where impurities and contaminants are removed, leaving behind pure H?O. This method involves boiling the water to produce steam, which is then cooled and condensed back into liquid form, leaving most of the dissolved minerals, salts, and microorganisms behind. Distilled water is widely used in various applications where high purity and contaminant-free water are required.