Biometrics

Biometrics uses measured human characteristics, such as fingerprint, face, iris or voice, to support recognition or authentication. A system stores a template derived from a sample rather than needing the original image for every comparison, but implementations differ. Biometric matching is probabilistic: false accepts and false rejects depend on thresholds, sensors, environment and population. A biometric trait is not secret or easily replaced if compromised, so it should not automatically be treated as stronger than every card or PIN. Design should cover liveness detection, fallback, enrolment, accessibility, retention, lawful purpose and template protection. Evaluation requires representative users and conditions, documented thresholds and monitoring of exceptions, not only a vendor accuracy figure.