Multi-factor Authentication FAQ - Multi-factor vs. two-factor
Although these refer to the same basic security practice, some accounts only allow you to enable a single, additional verification method. Depending on the account, this option may be called two-factor authentication (2FA) or two-step verification. Other accounts allow you to enable several methods simultaneously as fail-safes in case your preferred method is unavailable, which may be called multi-factor authentication.
Article Id #23505