The author of this manual has set his main task to give students and other readers a broad general overview of the problems, evidence and conclusions of extragalactic astronomy. Therefore, the presentation of such hypotheses as hypotheses about the structure of quasars and the origin of galaxies, hypotheses, moreover numerous, would create an enhanced impression of the obsolescence of the book. The book has a bias in the morphology of galaxies. The course of extragalactic astronomy can be of great help to the authors of theses and dissertations. For this purpose, a literature index is attached to the book, which is more extensive than in conventional textbooks. It can be assumed that this overview course will serve a wide range of scientists in contact with issues of extragalactic astronomy.