What is a authentication
The process of authentication aims to verify that someone or something is who/what they claim they are. The most used authentication service used in computer security is a username/password combination. Better forms of authentication will verify an identity by the use of a token, such as a swipe card or a smart card, or by biometric means, such as a retina scan, palm prints, or fingerprints.
Related terms:
Access control
Authorisation
Security mechanism