The word “biometrics” is derived from Ancient Greek and means the measurement (metrein) of living beings (bios). Biometric recognition methods refer to the technique of identifying a person on the basis of distinctive properties, such as their fingerprints, irises, hand veins or face. Facial recognition also plays a key part in the process leading to the joyous shout of “It’s a match” used by dating apps like Tinder: First of all, the features of a face are identified, usually on the basis of a photo, and stored as a set of data, known as a template. When a camera captures a person’s face for facial recognition purposes, the image is digitalised and stored, processed by recognition software and then compared with the records held in the database. If the system reports a match, what happens next depends on the context: either the doors to the maximum security wing open or an alarm is triggered at the police station.