A security method in which a user must provide two different forms of identification to gain access to a system or application. This method is also known as two-factor authentication. The two factors can be something the user knows (like a password), something the user owns (like a physical token or smartphone), or something associated with the user's physical identity (like a fingerprint or facial recognition). Using 2FA improves security by making it harder to gain unauthorized access, even if one factor (for example, the password) has been compromised.