Water is essential for life and makes up 70% of the human body. It is involved in many biological processes like digestion, circulation, and temperature regulation. Water can harbor various microbes like bacteria, viruses, and protozoa that cause diseases. Common waterborne diseases are typhoid, cholera, hepatitis, and diarrhea. Water is purified through various treatment methods to remove microbes. A significant percentage of foods also contain water, ranging from 100% in water to less than 1% in dry foods like nuts and cookies.