Authentication is the process used to verify the identity of a user or entity in a computer system. It’s a way to ensure that the person or thing trying to access a service, device, or network is who or what they claim to be. This is typically achieved through the use of passwords, biometric data (like fingerprints or facial recognition), security tokens, or a combination of these methods.

Authentication is the first line of defense in security.

Glenn Mulvaney, VP Cloud Operations at Clumio

In Simpler Terms

Think of logging into your email. You enter your username and password—that’s authentication in action. It’s the system’s way of verifying it’s really you, just like a bouncer checking your ID before letting you into a club. The concept of authentication goes beyond just passwords and biometrics. It can include things you have (like a security token or your phone), things you know (like a password or PIN), and things you are (like your fingerprint or face).