A retina scanner is a biometric device that identifies individuals by analyzing the unique patterns of blood vessels in their retinas, which are located at the back of the eyes. This technology uses infrared light to capture detailed images of the retina, making it a highly secure method of authentication. Retina scanning is often used in high-security environments, such as government buildings and data centers, to control access. Unlike other biometric systems, such as fingerprint scanners or facial recognition, retina scanners are less likely to be fooled by replicas, providing a higher level of security for sensitive information and areas.