Microorganisms make up a large part of the earth's biomass. They are of high importance in human, animal, and plant health. At the same time, microorganisms control environmental processes (degradation and synthesis of substances, biogeochemical cycles). The study course provides basic knowledge about the types, structure, basic principles of metabolism, classification, occurrence, and applicability in biotechnological processes. The study course also introduces various classical and modern laboratory methods for isolation, propagation, characterization, and identification of microorganisms.