Earth - the Water Planet

The earth is called the water planet because water in its liquid form covers more than 70 percent of its surface. But most of the water on earth isn't freshwater that we can drink or irrigate crops with. More than 97 percent of the earth's water is salt water in the oceans. That leaves less than three percent as freshwater. Two-thirds of that amount is locked up in glaciers and polar icecaps around the polar regions.

Half of what remains after that lies far underground and is too deep to be available for human use.