Joomla! Extensions Defined Joomla! already is a rich featured content management system, but if you're building a website with Joomla! and you need extra features which aren't available in Joomla! by default, you can easily extend it with extensions. There are five types of extensions for Joomla!: Components, Modules, Plugins, Templates, and Languages. Each of these extensions handle specific functionality. (Some built-in features of Joomla! are implemented using extensions.) Components Components are the largest and most complex extensions of them all; they can be seen as mini-applications. Most components have two parts: a site part and an administrator part. Every time a Joomla page loads, one component is called to render the main page body. For example, Content (com_content) is the component which handles the display of content; users can view at the frontend of your site and, as an administrator, you can edit the content. Components are the major portion of your page