Water filtration is a process that removes impurities from water by passing it through a filter or a series of filters. The filters used in water filtration can be made of materials such as activated carbon, sand, and gravel. The filtration process can also involve chemical treatments to remove specific contaminants from the water. Water filtration is an important part of ensuring safe drinking water, as it removes contaminants and improves the water's taste, smell, and appearance.