Two-Factor Authentication (2FA)

Two-factor authentication (2FA) is a security method that requires two different types of proof before granting access: something you know (a password or PIN), something you have (a phone, OTP or security key) or something you are (a fingerprint or face).

Even if a password is stolen, an attacker still needs the second factor. Common second factors include OTPs by SMS, authenticator apps that generate time-based codes (TOTP), push notifications and hardware security keys. Authenticator apps and security keys are more secure than SMS codes.