Beginner's Guide

Chapter 16
Plug-Ins
A plug-in adds specific capabilities to a component. The term plug-in is also used in other places. For
example, plug-ins are commonly used in web browsers to play videos. A well-known plug-in example is
Adobe's Flash Player. A good example for the use of plug-ins in Joomla is the Search component. Five
search plug-ins work together to find content from different Joomla components.
Joomla has eight plug-in types: authentication, captcha, content, editors-xtd, editors, extension, finder, quickicon,
search, system and user. These are also the names of the website sub directories where the plug-in files are
located. For example, plug-ins with a type of authentication are located in the website directory plugins/
authentication. It is not possible and not necessary to create a plug-in in the adminstrator area like we have
seen in the modules chapter. A plug-in has to be installed via the Extension Management.
AUTHENTICATION
Authentication in Joomla is the process of verifying7 whether a user should be7 permitted to do
something7on the site. Authorization, which is always the process that follows authentication, verifies that
an authenticated user has permission to do something. You authenticate with your username and
password, and you are authorized by being a member of a permission group. (read more: Users and
Permissions). Joomla offers three possibilities7 for authentication7 (Figure 1). Be careful with deactivating
plug-ins. You must have at least one authentication plug-in enabled or you will lose all access to your site.
Figure 1: Authentication Plug-ins
Joomla
The plug-in provides the standard behavior for Joomla. You fill in the login form with your username
and password and your login information is then verified.
Joomla! 2.5 - Beginner’s Guide
Monday, 30 January 2012! Page 181