Why are the water filters useful in a house and apartment?

Individual filters and water filtration systems for residential applications are not only useful but necessary in every home and apartment. Their main purpose is to filter (remove and block pollutants) and treat (improve taste, odor and mineral content) tap water to such an extent that it does not constitute any smallest threat to human health. 

The use of filtration systems is particularly desirable in buildings equipped with outdated plumbing systems and supplied with chlorinated and deep well water as well as waters from agricultural areas.