What does Login with Facebook mean?
Facebook Login allows visitors to use their Facebook profile to log into your website instead of creating a unique sign-in. Then, when a visitor uses Facebook to log in, they also grant you access to specific pieces of information. That information may include their: Email. Public profile.
How does Login work on a website?
The process is fairly simple; users input their credentials on the website's login form. That information is then sent to the authentication server where the information is compared with all the user credentials on file. When a match is found, the system will authenticate users and grant them access to their accounts.