The cryptocurrency community is all about advocating proper security techniques, and two-factor authentication (2FA) is one method that’s taught first and foremost to newcomers. 2FA is a subset of multi-factor authentication (MFA), a system that requires the use of two different factors to unlock a combination. For example, if 2FA is applied to a cryptocurrency exchange account you would need to log in with your username and password, but you will also need to enter a 2FA authentication PIN. The authenticator is usually on a secondary device like a mobile phone or a USB key.
https://blog.kucoin.com/crypto-exchange-security-best-2fa-apps-for-crypto-sk-st