The book is devoted to the central problem of astronomy in the physics of stars . The final stage of stellar evolution is of particular interest, as it is directly related to such interesting objects of modern astronomy as pulsars, X-ray stars and black holes. The problems associated with these objects are still far from being solved. Therefore, the author sought to highlight the actual state of the question, giving only a general idea of the existing theories and hypotheses. The book also deals with the problem of star formation .. The book is intended for a wide range of people with secondary education .. It is of special interest for students, lecturers, teachers, specialists in related sciences.