Distilled water is water that has many of its impurities removed through the process of distillation. Distillation involves boiling the water and then condensing the steam into a clean container; impurities dissolved or suspended in water cannot transform to vapor phase with water, so they are left behind in the “brine”. Water that has been distilled is ultra-pure, and may taste flat compared with other water, so it is generally not used for drinking purposes. Distilled water is frequently used for medical, dental, or industrial processes.  Some bottleless water coolers offer distilled water, which may be convenient and cost-effective for low-volume applications.