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 HelpSEF HelpDebug HelpDefault off:Cache HelpLog HelpRedirect Help
User Default on:Joomla HelpDefault off:Two new plugins are available in 1.6 but are disabled by default.Contact Creator HelpCreates a new linked contact record for each new user created. Profile HelpThis 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.