Biometric technologies use physical characteristics, such as voice tone or hand shape, to identify people automatically. Behaviors, such as handwriting style, can also be used by computers in this way. The term “identify” is used here quite loosely. There is actually nothing in your voice, hand shape or any biometric measure to tell the computer your name, age or citizenship, or to establish your eligibility to vote. External documents (passport, birth certificate, naturalization papers) or your good word establishing these facts must be supplied at the time you initially present yourself to the biometric system for “enrollment”. At this initial session, your biometric characteristic, such as an eye scan, is recorded and linked to this externally-supplied personal information.