Getting essential information on the Fundamental aspects of microbiology with concepts of microbial diversity, taxonomy, morphology, physiology, and their other features is necessary to understand about the life of the various group of microorganisms. Therefore, in this book indicates these scopes of microbes with their different symbiotic associations including the clinical and epidemiological aspects of Infectious diseases so that it serves as subject matter for all students of microbiology at different levels as well as to individuals interested to get some knowledge on the life of pathogenic microorganism, especially those like the Bacteria, fungi, protozoa and viral groups.