Glossary
Biometric Template
A biometric template is a mathematical representation extracted from a raw biometric scan — a fingerprint, a face — and stored for later comparison, rather than the raw image or scan itself. A well-designed template is derived in a way that isn't reversible back into the original raw biometric, which matters specifically because a biometric characteristic can't be changed the way a compromised password can: if the raw data itself leaked, there's no way to issue the person a new fingerprint.
This is why storing a genuinely irreversible template, rather than the raw biometric data, is the deliberate design choice worth insisting on: a leaked template is a real problem, but a leaked raw fingerprint is a permanent one, and the two failure modes have very different consequences for exactly the population whose biometric data was exposed.