Active Galactic Nuclei and Galactic black holes in brief -------------------------------------------------------- In my lectures I am going to give an introduction to active galactic nuclei (AGN) and Galactic black hole candidates (GBHCs). Starting with the observational appearance in various spectral bands we discuss the classification of AGN and GBHCs. We explore the most recent models to explain the variety of objects that is observed. In this context, I briefly cover selected topics of accretion physics and radiative processes: standard accretion disk model (alpha-disk), magnetic flares, radiative transfer equation and methods to solve it. The lectures will be given in English.