After activating it, you'll have to type in a 6-digit verification code generated by Google Authenticator or other authenticator apps when you log in. Since Reddit's two-factor doesn't rely on SMS and doesn't ask for your phone number, you'll have to attach an email address to your account. You'll also have to verify it, so you'll have a way to reset or recover your account if you lose your phone. If the feature sees widespread adoption, then Redditors might be more conscious of their security than the average internet user -- less than 10 percent of all Gmail accounts, for instance, have enabled two-factor authentication.