The authentication plugins operate when users login to your site or administrator. The Joomla! authentication is in operation by default but you can enable Gmail or LDAP or install a plugin for a different system. An example is included that may be used to create a new authentication plugin.
Default on:
- Joomla
Default off:
- Gmail
- LDAP
Editors are used thoughout Joomla! where content is created. TinyMCE is the default choice in most locations although CodeMirror is used in the template manager. No Editor provides a text box for html content.
Default on:
- CodeMirror Help
- TinyMCE Help
- No Editor Help
Default off:
- None
These plugins are behind the buttons found beneath your editor. They only run when an editor plugin runs.
Default on:
- Editor Button: Image
- Editor Button: Readmore
- Editor Button: Page Break
- Editor Button: Article
Default off:
- None
The search component uses plugins to control which parts of your Joomla! site are searched. You may choose to turn off some areas to improve performance or for other reasons. Many third party Joomla! extensions have search plugins that extend where search takes place.
Default On:
- Content Help
- Contacts Help
- WeblinksHelp
- News FeedsHelp
- CategoriesHelp
Subcategories
Components
Components are larger extensions that produce the major content for your site. Each component has one or more "views" that control how content is displayed.In the Joomla! administrator there are additional extensions suce as Menus, Redirection, and the extension managers.
Modules
Modules are small blocks of content that can be displayed in positions on a web page. The menus on this site are displayed in modules. The core of Joomla! includes 17 separate modules ranging from login to search to random images. Each module has a name that starts mod_ but when it displays it has a title. In the descriptions in this section, the titles are the same as the names.
Plugins are small task oriented extensions that enhance the Joomla! framework. Some are associated with particular extensions and others, such as editors, are used across all of Joomla!. Most beginning users do not need to change any of the plugins that install with Joomla!. 
