It's kind of like the earth is a big sponge holding all that water.
Water can also move through rock formations like sandstone or through cracks in rocks.
An area that holds a lot of water, which can be pumped up with a well, is called an aquifer . Wells pump groundwater from the ground and then pipes deliver the water to cities, houses in the country, or to crops. The Groundwater Foundation. This page last updated January 2000.