Extensions
Syndicate Module
The syndicate module allows you to display a link that allows users to take a feed from your site. It will only display on pages for which feeds are possible. That means it will not display on single article, contact or weblinks pages, such as this one. Help
System
System plugins operate every time a page on your site loads. They control such things as your URLS, whether users can check a "remember me" box on the login module, and whether caching is enabled. New in 1.6 is the redirect plugin that with the redirect component assist you in managing changes in URLs.
Default on:
- Remember me Help
- SEFHelp
- DebugHelp
Default off:
- CacheHelp
- LogHelp
- RedirectHelp
User
Default on:
- Joomla Help
Default off:
Two new plugins are available in 1.6 but are disabled by default.
- Contact CreatorHelp
Creates a new linked contact record for each new user created. - ProfileHelp
This example profile plugin allows you to insert additional fields into user registration and profile display. This is intended as an example of the types of extensions to the profile you might want to create.
Users
The users extension lets your site visitors register, login and logout, change their passwords and other information, and recover lost passwords. In the administrator it allows you to create, block and manage users and create user groups and access levels. Help
Please note that some of the user views will not display if you are not logged in to the site.
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.
Templates give your site its look and feel. They determine layout, colors, type faces, graphics and other aspects of design that make your site unique. Your installation of Joomla comes prepackaged with four templates. 
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!. Easy to Start
Tutorials and Online Training create for the analyzers & students involve into the ATLAS Experiment
Monitoring Tools of ATLAS Napoli Team
In addition ATLAS Napoli team develops tools to monitoring differnet aspects of the ATLAS experiment.