How did the first living beings on Earth exist? Why is a frog green? How does a fluorescence microscope work? How much energy does a bacterium need to double? From the basics of metabolism to the diversity of microorganisms and the processes in the ocean or during an infectious disease, Heribert Cypionka explains the fundamental connections of microbiology using clear examples and images. The book offers an ideal introduction to microbiology: compact yet challenging, it conveys essential subject knowledge without getting lost in details. Questions at the beginning and a glossary of key terms at the end of each chapter assist with exam preparation. The edition has been thoroughly revised and for the first time includes many color images. The diversity of microorganisms is presented in nearly 300 pages.