Biometrics -- the science of using the body to identify a person -- is everywhere, not just in science fiction, but in everyday life. Today, biometrics is on the cutting edge of security. It's used for access into banks and airports, as well as to keep money and personal information safe. Methods like fingerprinting and retinal scanning might be more familiar, but biometrics can also identify people based on ear shape, scent, vein pattern, and much more. This book explores nine biometrics in detail, explaining how each works, where it's used, its pros and cons, and how it compares to other techniques. It also discusses privacy, security, why we need methods of identification, and touches on biometrics of the future. Engaging and colorful design and playful illustrations alongside surprising anecdotes, historical context, and humor make this an enjoyable, in-depth look at a hot topic. Informational text features include sidebars, diagrams, sources, a glossary and an index.