[sslnx]

Fingerprint scan and Facial recognition can not replace password authentication because both face and fingerprint are public information, while password is meant to be private. You cannot hide your face or fingerprint from others.

[majewsky]

As a rule of thumb (pun not intended), biometric data is a username, not a password.

[kiriakasis]

Disagree. It is not a password for sure, but not even a username. biometrics are an indentifier.

username/password split an unique/secure identifier in a unique part and a (supposedly) secure part. biometrics are that pair together.