Basic PHP as you stated is not enough to even begin with. You definitely need to know how to handle arrays and MVC. This gives you an introduction to that: http://xenforo.com/community/threads/great-tutorial-for-basic-php-from-zend-devzone.29661/ It will take you one hour to learn the basics for MVC and then you'll understand the xenforo code much better. The tutorials from Fuhrmann in the Resource Manager are very good. Here you can even dive in with basic PHP. I'd say, take the small one hour tour from the link I posted here and then go through Fuhrmanns tutorials.