User levels as described in the Joomla manual
http://help.joomla.org/images/User_manual/user_manual_v1%200%201_10%2021%2006.pdf (opens new window)
Table 4: Front-end Registered Users
User Access & Permissions
A Registered User has no ability to create, edit, or publish content on a Joomla! web site.
Registered They may submit new Web Links for publication and they may have access to restricted content that is not available to guests.
Author Authors can create their own content, specify certain aspects of how the content will be displayed, and specify the date when the material should be published.
Editor Editors have the same abilities as an Author and they can edit their own content as well as that of any other Author.
Publisher Publishers can perform all the duties of Authors and Editors and have the ability to publish content.
The default user role is Registered User. For Front-end users to receive any other role requires
an Administrator or Super Administrator to change their profile through the Back-end
Administrator panel.
Back‐end Users
Back-end users — Managers, Administrators, and Super Administrators — are typically thought of
as the site administrators, but they also have access to the Front-end interface. Just as with the
Front-end Users, Back-end Users may have different privileges.
Table 5: Back-end Registered Users
User Access & Permissions
Manager
A Manager has the same permissions as a Publisher but with access to the Backend
Administrator’s panel.
Managers have access to all the content associated controls in the administrator
panel but are not able to change templates, alter page layouts, or add or delete
extensions to Joomla!
Managers also have no authority to add users or alter existing user profiles
Administrator
Administrators have a broader range of access than Managers do.
Administrators can add and delete extensions to the web site, change templates or alter page layouts and can even alter user profiles equal to their own permission levels or below. What they cannot do is edit the profiles of a Super Administrator or change certain global characteristics of the web site. Super Administrators do not show up in the User Manager screen when users are ogged in as an Administrator.
Super Administrator
The Super Administrator has the same kind of power as root in a traditional Linux
system and has unrestricted abilities to perform all administrative functions inside
of Joomla! Only Super Administrators have the ability to create new users with
Super Administrator permissions or to assign Super Administrator permissions to
existing users.
The only user that exists after a Joomla! installation is the Super Administrator. This is the ‘admin’
account created during the installation process.