The document discusses the inner workings of Zend Framework, including its use of .htaccess and index.php files to bootstrap the application. It describes how Zend/Application/Bootstrap/BootstrapAbstract.php and application-specific bootstrap files are used to initialize the application. The front controller pattern is implemented using Zend/Application/Resource/Frontcontroller.php. Routing is handled by Zend/Controller/Router modules which dispatch requests to controllers and actions. While the framework aims to be simple through convention over configuration, it can also be complex under the hood. Zend Framework 2 refactored some components, such as the database adapter, for improved architecture.