You may have noticed that plug-ins are grouped into different types in the Plugin Manager. These different types operate in different areas of Joomla and at different points of the rendering process. Each plug-in type dispatches its own triggers, so let’s go over them in detail from a user’s perspective—even if some of it gets a little “geeky.”
When users log in to your website, their login credentials are verified against the users that are registered on the website. If you wanted someone to be able to log in using a Google account, you’d want to enable the Authentication–GMail plug-in. When someone tries to log in, her username and password will be verified by Google using its API. If she logs in successfully, an account with the same login credentials will automatically be created in Joomla.
The only authentication trigger that can be dispatched is onAuthenticate.
You should never disable the Authentication–Joomla plug-in. Doing so will prevent users from logging in to your site. This even includes Super Administrators. If you accidentally disable it and can’t log back in, change the published field in the jos_plugins table to 1 for the Authentication-Joomla record. You will most likely need to use phpMyAdmin, a tool for managing MySQL tables, to accomplish this. If you don’t know how to access it on your website, contact your hosting provider for assistance.
These plug-ins only affect articles. Content type plug-ins allow you to add functionality ...