Two-Factor Authentication (2FA)
Two-factor authentication (sometimes called 2FA for short) is an added layer of security for your account beyond the standard email/password authentication. By registering a trusted device (ie. your phone) with your account, access to your account becomes secured by requiring both something you know (ie. your password) with something you have (ie. your phone).
To set up two-factor authentication, you'll first need to download and install an authentication app onto your device such as Google Authenticator (iOS or Android) or Authy (iOS or Android).
Next, visit the account settings page and under the section labeled "Security", click "Enable". You'll be prompted to scan a QR code with your authenticator app. This process stores a secret token onto your device which is combined with the current time of day to generate a time-sensitive 6-digit code that will be used verify possession of the device. Enter the current 6-digit code to register the device with your account. After your device is registered, you'll be asked to enter in a new 6-digit code generated by your authenticator app every time you log into your account.