In every use of computers to solve human problems, a central and crucial factor is the flow of information and control between human and machine. HCII leads also to a human-centered approach for the design of intelligent systems as it helps with creating a richer, more versatile, and effective virtual environment that supports human activity. The goal of this effort is to develop the science and technology of verifying a person's identity. Biometric measures the physical characteristics that make each of us unique, like the fingerprints, an eye's retina or iris, a face, a hand, a voice - and uses those measurements to confirm personal identity.
Passwords are difficult to remember and easy to steal.
Keys, driver's licenses and passports can be lost or forged. The human body, on the other hand, can't be forgotten, stolen, forged or misplaced. Practical uses for such biometrics are wide spread and include maintaining the security for both physical space and cyberspace. In particular, biometrics helps with controlling access to an office, a lab, or ATM, confirm the identity of buyers and sellers, protecting company networks from hackers, make electronic commerce safe and reliable, confirm student identity for distant learning and examinations, and keeping medical records on the web private. As face recognition technology requires little or no cooperation from the subject, it is becoming one of the top choices for biometrics and is starting to move into the commercial market.