Two-Factor Authentication (known as TFA or 2FA) is a security method used to access an account or service that requires you to provide two pieces of data to successfully authenticate. When 2FA is enabled you can only log in with both your original password and an additional code generated by your 2FA method.

The most popular 2FA methods are SMS authentication and app based authentication where you receive a code via SMS to your registered phone number or via a third party app like Authy or Google Authenticator (using the internet instead of SMS).