Biometrics
is the biological identification of a person, including iris and retinal patterns, hand geometry, fingerprints, voice responses to challenges, and the dynamics of hand-written signatures. Biometrics are a more secure form of authentication than typing passwords or even using smart cards, which can be stolen; however, some forms have relatively high failure rates.
From :www.securemethods.com/glossary.htm

Biometrics utilize "something you are" to authenticate identification. This might include fingerprints, retina pattern, iris, hand geometry, vein patterns, voice password, or signature dynamics. Biometrics can be used with a smart card to authenticate the user. The user's biometric information is stored on a smart card, the card is placed in a reader, and a biometric scanner reads the information to match it against that on the card. ... From:www.idwholesaler.com/resources/dictionary.htm