This chapter introduces the field of microbiology and
discusses the importance of microorganisms not only as causative agents of disease
but also as important contributors to food production, antibiotic manufacture,
vaccine development, and environmental management. It presents a brief history
of the science of microbiology, an overview of the microbial world, a discussion
of the scope and relevance of microbiology in today's society, and predictions
about the future of microbiology.