What Are
Extensions?
Extensions are installable packages
that extend the core functionality of Joomla in some way. There are five types
of extensions:
- Components— A component is the most
complex type of extension. It is some sort of mini-application that
usually renders content in the main body (large middle column) of the
page. The core content component (com content), for example, is the
mini-application that shows all your articles in some way. Another example
might be a forum component that shows boards, threads, and so on. Not all
components are about content; some handle a complex function. For example,
the registration component (com registration) handles user registration.
- Modules— Modules are usually
much smaller and less complex than components. They also usually appear
around the edges of the main body, in the header, side columns, or footer
and are small extensions that do small tasks. For example, the Latest News
module shows links to the most recent articles that have been added to the
site. Often, a module will work with a particular component. For example,
the login form module allows site visitors to log in to the site.
- Plugins— A plugin (formerly called
mambot) is a special piece of code that can be used across the site and
runs when a page is loaded. An example is the email cloaking plugin, which hides
email addresses with JavaScript so spam robots cannot see them.
- Templates— Templates
control the graphical look and feel of the site. They usually include colors,
graphics, and typography.
- Languages— By installing a
language pack, it is possible to internationalize Joomla to a different
language. All of the words that are part of Joomla (like where it says
"Read More") will be displayed in the chosen language.