Earth

There is a reason the Earth looks so blue, 70% of the Earth’s surface is covered in water. Water is an essential part of life for all creatures on the planet, from the tiniest bacteria to the tallest tree. None of us could survive long without it.

You have probably heard water referred to as H2O. This is because water is made up of three atoms - two hydrogen atoms (H2) and one oxygen atom (O).

Water is found in three different forms: as a liquid, a solid (ice), and a gas (water vapour). As a liquid we bathe in and drink it, as a solid it keeps our drinks cool, as a gas it blankets the Earth keeping it warm.

Next: How Much Is There?

Adapted from Pollution Probe's Drinking Water Primer