===Note on Acronyms===
Here and in several other documents you see many acronyms that are associated with the notion of a second means of authentication. This is a non-exhaustive list:
|**Acronym**|**Description**|
|MFA|Multi Factor Authentication. You will need to identify yourself using an additional, independent from account password, means, such as a 6 digit code or smartphone app|
|2FA|Instance of MFA with only one additional means of authentication|
|OTP|One time password|
|One time password|A usually additional password that you need to give in order to authenticate and be allowed to login |
|TOTP|Time-based one time password|
|Time-based one time password|A usually addition password, which is valid for a limited amount of time, that you need to give in order to authenticate and be allowed to login|
|HOTP|Event-based One-Time Password|
|Event-based One-Time Password|A usually hardware based additional means of authentication, sometimes implemented using USB keys|
|OATH|Open Authentication TOTP HTOP is a protocol defintion on how to use TOTP (or HTOP)|