- Biometrics refers to the quantifiable data (or metrics) related to human characteristics and traits. Biometrics identification (or biometric authentication)[note 1] is used in computer science as a form of identification and access control. It is also used to identify individuals in groups that are under surveillance. Biometric identifiers are the distinctive, measurable characteristics used to label and describe individuals. Biometric identifiers are often categorized as physiological versus behavioral characteristics.