Bacteriology course is an introduction to the study of bacteria and their interrelationships with humans and environments. General bacteriology concepts such as bacterial structure, growth, and control of bacterial growth are applied to such medically, biological and agricultural related topics as control and pathogenicity of bacteria. The Chapters concern phylogeny of prokaryotes, structure, function, growth, control of growth, regulation of enzymes, and environment. Bacteriology should be taken by students majoring in basic biological sciences such as biochemistry, genetics or molecular biology, botany as well as by students planning careers in medicine, veterinary sciences, agriculture or pharmacy. The text is supplemented by boxed items of the objectives and special interests or activity, and each chapter concludes with a useful for quick revision as well as self-assessment questions to provide summative evaluation of what readers have learned. The goals of this book to present lectures in a simple form giving the required information that may help to increase the undergraduate readers.