Biometrics are the measurement of the unique physiological or behavioural characteristics of the human body, such as the finger print or iris pattern. Most often, biometrics are used to identify an individual in situations requiring high levels of accuracy or in scenarios allowing human interaction with computers.

The different varieties of biometrics are:

Speaker Verification: This biometric can be used to verify the identity of a person or to allow an individual to interact with a machine, such as in an automated call centre.

Finger Scanning: This technique can be used to identify an individual from the print on the pad of their finger (or a combination of their fingers). It is most often used to restrict physical or virtual access.

Palm Scanning: This technique takes certain measurements from the palm print of the individual. It generally requires the participant to claim an identity against which the palm print can be identified. This biometric is very popular for time and attendance machines.

Iris/Retina Recognition: This biometric measures the unique pattern of a person's iris or retina by an electronic scan. It is extremely accurate and is generally used to restrict physical access.

Signature Verification: Various electronic measurements are taken from the person writing their signature to produce an accurate assessment of their identity.

Face Recognition: This biometric takes various measurements of the human face as captured on video to compare them with an existing template of faces and make a match. This form of biometric is growing in popularity in airports.

Other forms of biometrics yet to make a substantial impact in the commercial arena include those measuring body odour, typing characteristics, ear shape and gait.