Groundwater (or ground water) is water located below the ground surface. Groundwater starts as rain (or other precipitation), and flows under ground for long periods of time through aquifers. Groundwater flow returns to the surface again through springs and rivers. Groundwater is an important part of the water cycle.
People drink groundwater with water wells. They drill wells deep below the surface. Then, in the aquifer, the groundwater stored inside will be pumped up and used.