What is the Process of Verifying the Identity of a User called?

Question: What is the Process of Verifying the Identity of a User Called?

Answer: Authentication.  

Authentication is verifying the identity of a user or computer system. The authentication process is done to verify that the person using the system or requesting access to it is who they claim to be. The mechanism of authentication is associated with an incoming request along with a person identifying credentials. Authentication can be done by various means, including something you know (a password), something you have (a token), or something you are (biometrics). The term can also refer to the process of verifying that the parties involved are who they claim to be.