What is Two-factor authentication?

A second proof of identity beyond a password — an authenticator app, hardware key, or code — so a stolen password alone isn't enough to get in.

How it works

Passwords leak through breaches and phishing; 2FA blunts that. A hardware key or authenticator app beats SMS, which is vulnerable to SIM-swap. On a hardened system, enable it on every account that offers it.

Example

In practiceYou secure your email and key accounts with an authenticator app or hardware key, not SMS, so a phished password can't get an attacker in.

SMS, app, or hardware key?

Hardware key or authenticator app — both resist phishing and SIM-swap. SMS is better than nothing but the weakest option.

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