"Bergey's Manual of Systematic Bacteriology" is a comprehensive reference book that focuses on systematic bacteriology. It provides a detailed introduction to the classification of prokaryotes and covers fundamental concepts such as the definition of bacterial species and various approaches to taxonomy, including numerical and polyphasic methods. The book also includes important information on bacterial nomenclature and the etymology of prokaryotic names. Additionally, it discusses the application of nucleic acid probes in environmental microbiology, the significance of culture collections, and intellectual property related to prokaryotes. A notable feature is the first Road Map to Prokaryotes, which offers an overview of the phylogenetic framework and the taxonomic structure for the systematic classification of prokaryotes.