The element H2O is water. Water is comprised of two parts hydrogen and one part oxygen. It was discovered by chemist Henry Cavendish.
Cavendish discovered how hydrogen and oxygen worked together when he took the two and mixed them together. The reaction was an explosion called the oxyhydrogen effect. In 1811, Italian physician Amadeo Avogadro found the formula for water. It didn't take long for him to understand that water is the only element that can exist as a solid, gas and liquid.
Since the first discovery of water, much has been learned about the element. It is a bad heat conductor and an excellent solvent and means of transport. Without water, life on Earth would cease to exist.