Modules are the core of Magento. Every action on the site, frontend or backend, goes through a module. Modules act as containers for one or more of the following: settings, database schemas, rendering objects, utility helpers, data models, or action controllers. A module can be made of all six of these things, or just one. Modules are defined as being on or off in an XML configuration system located in app/etc/modules/. Each module can specify its own settings in an XML file as well, located under themodule’s etc/ directory. Since everything in Magento is a module, and modules have self-contained configuration and database settings, this allows you, as a developer, to extend Magento exactly as the core system is built . Module Structure: · Module and Default Directories All models exist under a package directory. The package serves no purpose other than to allow for consistent naming of classes. All Magento modules are part of the Mage pac