The book provides generalized modern information about all groups of living fish and jawless, as well as about many fossil taxa. Each of the 515 families of modern fish is characterized briefly, but exhaustively - data on distribution and biology are given, a clear morphological diagnosis is given, the internal taxonomic structure is described, and the number of genera and their list are given. The book has more than 480 graphic illustrations that give an idea of ​ ​ the general external morphological appearance of almost every discussed group. In addition, the Russian translation includes a reference dictionary of used terms prepared by the translator and scientific editors.