Groundwater is an important source of water. It is the water present in the deeper layers of soil below the water table. Some of the important sources of groundwater are rainfall, rivers, ponds, etc. When it pours, water goes down in the soil layers to fill the spaces present below the ground. When the groundwater is accumulated between the hard rock layer, it becomes aquifer. The aquifers serve as a source of fresh water as the water present in them can be pumped out using techniques such as tube wells.