Here put some important information & pictures.
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:
Default on:
Default off:
Two new plugins are available in 1.6 but are disabled by default.
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. Â New in 1.6 is the redirect plugin that with the redirect component assist you in managing changes in URLs.
Default on:
Default off: