(n.) Generally, the study of measurable biological characteristics. In computer security, biometrics refers to authentication techniques that rely on measurable physical characteristics that can be automatically checked.
There are several types of biometric identification schemes:
Though the field is still in its infancy, many people believe that biometrics will play a critical role in future computers, and especially in electronic commerce. Personal computers of the future might include a fingerprint scanner where you could place your index finger. The computer would analyze your fingerprint to determine who you are and, based on your identity, authorize you different levels of access. Access levels could include the ability to use credit card information to make electronic purchases.
See "Defend Yourself Against Identity Theft" in the "Did You Know..." section of Webopedia.
See also "How Biometrics Security Works" in the "Did You Know..." section of Webopedia.
Also see "How Fingerprint Scanners Work" in the ""Did You Know..." section of Webopedia.