Read the Introduction or Start here. On any page you can use the links in the navigation box above.
You need Joomla! 2.5 (with PHP, MySQL, Apache and Microsoft II) or greater for this tutorial.
It will help you much if you are running an local instance of Joomla on your computer. Then backup librarys map tree and put in your own debug code there. Very much tracing can be done in controller and view code. You can put a lot of 'error_log(...)' and you can also combine it with 'print_r(debug_backtrace(),true)' to get a better understanding of what really happens behind the surface. You will be able to follow your programs steps in apache's error log.
Joomla! 2.5 is constructed using three different applications:
The installation application is used once. The administrator and public are used through the concept of components. Each component has two entry points:
Both are called com_componentname/componentname.php (the com_ prefix is a historical trace)