Two-factor authentication (2FA) is a security method that requires two separate forms of verification before granting access. Typically, the two factors include something the user knows (password), something they have (phone or hardware token), or something they are (biometrics). 2FA significantly reduces the risk of unauthorized account access.
Why it matters
Passwords alone are often weak or reused, making accounts vulnerable. 2FA provides an additional layer of protection and is a critical best practice for both personal and enterprise security.
Examples
Entering a password and then a one-time code sent via SMS or generated by an authenticator app. Lessons on authentication deep dives reinforce 2FA concepts.