Logging in with a password is single-step authentication. It relies only on something you know. Two-step authentication, by definition, is a system where you use two of the three possible factors to prove your identity, instead of just one. In practice, however, current two-step implementations still rely on a password you know, but use your phone or another device to authenticate with something you have.

If you want to secure your site or an app, you can implement 2fa (Two factor authentication) in your site in few minutes. Just simply copy and paste the code below in any text editor.