Facebook recently updated their PHP-SDK to version 3.0 also added new way of authentication. This is a major change. So this is the updated post of my old popular post.
In this version of my code, I avoided javascript authentication, because that is cookie based and php sdk 3.0 has some conflicts with the old system. Facebook will also update the javascript sdk soon, so later you can use the login/logout system of javascript api with php sdk. But for now you should use fully php base authentication.
✓ How to integrate Facebook Connect in your website
✓ How to generate Facebook Login / Logout URL
✓ How to get extended permissions from users
✓ How to call graph api
✓ How to run FQL Query
✓ Publish Wall Post using PHP
✓ Publish Wall Post using Facebook Javascript API
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✓ No Facebook Javascript only use PHP SDK