Two-factor authentication with TOTP applications
Many websites and online services offer two-factor authentication (2FA) using SMS or using a Time-based One-Time Password (TOTP) application (some services also offer an email link, but I will not cover it here, although it also adds security in a similar way). It is highly recommended to use two-factor authentication to sign in to websites. It adds one layer of information besides the password, which makes signing in to online websites a bit more secure. The only way someone can get into your account is if they acquire both your password and the secret key on your phone. I prefer TOTP over SMS, because SMS is sometimes more unreliable and slower. (I won't discuss which method is more secure; there are potential vulnerabilities in both use cases depending on device and platform) Time-based One-Time Password A Time-based One-Time Password algorithm calculates a one-time password from a shared secret key and the current time. It is a standard described in RFC 6238 . It re...