MFA (Multi-Factor Authentication)

A security mechanism that requires users to provide two or more independent verification factors from different categories to prove their identity: something they know (password, PIN), something they have (hardware key, authenticator app, SMS code), or something they are (biometric). MFA dramatically reduces the impact of compromised passwords because an attacker also needs the second factor. TOTP apps and FIDO2 hardware keys are the most phishing-resistant options.