This acronym stands for "Two-Factor Authentication". The password is your first factor, and the second factor secures your authentication.
There are several types of second factors possible:
- A username or a second password
- A phone to receive a text message containing a code
- A phone with an application that generates a code
- A biometric identification with a fingerprint
While this will never completely guarantee a hack, it is highly recommended to enable it on a trading platform. Google Authentificator and Authy applications allow to generate codes easily and this method is more secure than SMS.
