What is: MFA (multi-factor authentication)

MFA requires a second proof beyond the password — such as a one-time code or a confirmation on your phone — so a stolen password alone is not enough to get in.

Most account breaches start from a stolen or guessed password. MFA adds a second "key" that only the real user has, blocking the vast majority of these attacks.

It is one of the most cost-effective security measures: low cost, large protection. In Microsoft 365 it is enabled for everyone and combined with Conditional Access.