The sometimes insidious effects of bacterial diseases and viral infections can obscure the incredible significance of the microscopic organisms that cause them. Bacteria and viruses are among the oldest agents on Earth and reveal much about the planet's past and evolution. Moreover, their utility in the development of new cures and treatments signals much about the future of biotechnology and medicine. This penetrating volume takes readers under the lens of a microscope to explore the structure, nature, and role of both bacteria and viruses as well as all other aspects of microbiology.