This text deals with the species of the natural family of dogs that no longer occur in the wild today, particularly with the species that zoologists and laypeople collectively refer to as "the domestic dog." Its purpose is to comprehensively and exhaustively address all the main forms of the domestic dog as well as all previously described variations and breeds. It aims to serve as a compendium that provides sufficient information on all questions regarding the nature of the domestic dog, its characteristics, uses, history, etc., and offers friends of this animal, which is so important to humans, the opportunity to navigate the vast number of variations and breeds for accurate identification.