The Quick Icon plugin group is used to provide notification that updates to Joomla! or installed extensions are available and should be applied. These notifications display on your administrator control panel, which is the page you see when you first log in to your site administrator.
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.
The Captcha plugins are used to prevent spam submissions on your forms such as registration, contact and login. You basic installation of Joomla includes one Captcha plugin which leverages the ReCaptchaÂ® service but you may install other plugins connecting to different Captcha systems.
- ReCaptcha help
Note: ReCaptcha is a the trademark of Google Inc. and is an independent product not associated with or endorsed by the Joomla Project. You will need to register and agree to the Terms of Service at Recaptcha.net to use this plugin. Complete instructions are available if you edit the ReCaptcha plugin in the Plugin Manager.
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 is the redirect plugin that together with the redirect component will assist you in managing changes in URLs.