This book talks about household filters and water purification systems. Information on the quality of water in water bodies of various regions of Russia on the possible undesirable consequences for humans of the use of untreated water, as well as recommendations on the choice of a household filter, are presented. Information on the main properties of water, conditions for the formation of the chemical composition of natural water, sources of pollution of water bodies, requirements for the quality of drinking water are presented. Here you will learn about the technologies for preparing drinking quality water from ancient Rome to the present day. You will find a description of water treatment methods and the design of more than 100 filter models.