Two factor or multi factor authentication adds an additional security layer to your usual method of logging into a system be it E-mail, Remote Desktop and any other type of account that requires you to login. This type of authentication is not a new method of authentication but is becoming a more popular method due to insecurities in current login methods.
It has become commonplace for scammers to have access to your details via email phishing scams or via previous account hacks or even brute force hacking weak passwords on accounts. If you have always kept the same password or similar for all accounts you hold this makes it easier for an unauthorised person to gain access to your account and personal information contain within.
How does it work?
Two factor authentication thwarts these attempts of unauthorised accessed by using an app or authentication code sent to your mobile device or separate account which you only have access to.
Usually the sign in from a two factor for email is remembered until a new device is attempting to use the account. Say if you have two factor authentication set up on your phone, it will only ask at specific time periods or when a new phone is used to access the account or when a time out of the authenticated device occurs.
For other device logins such as Remote Desktop the Authentication code is asked for at each login attempt.
Having two factor authentication is important as it acts a road block to those who would otherwise been able to access your account. It is virtually impossible to access your account with two factor authentication enabled without having access to your authentication device such as your phone or tablet. While it is almost impossible for your account to be accessed by an unauthorised person while two factor is enabled it is not guaranteed and a good complex password should still be set on your account.
Which method should I use?
The authentication method you choose to use depends on the level of security you wish to implement and are comfortable with using.
Receiving a code via a secondary email account is the least secure and not recommended as this secondary email account could very well be compromised just as easily as any other email account.
Receiving a code via SMS is the next secure method but can also be comprised if you happen to have your phone’s sim cloned somehow.
Receiving a code via an authentication app on your phone is the most secure method of verifying you are indeed you when signing into your account.