Alter Glossary

In Joomla! an Article is a piece of content consisting of text (HTML), possibly with links to other resources (for example, images). Articles are the basic units of information in the content system and the bottom level in the content hierarchy. Since Joomla! 1.6 , each Article is in exactly one Category, and Categories can be in other Categories. It is also possible to have Uncategorised Articles that exist without being associated with any Category.

In Joomla! a Category is a collection of Articles. In Joomla! versions up to and including , is the middle level in the hierarchy Sections -> Categories -> Articles. For example, a website might have Sections called "Animals" and "Plants". Within the "Animals" Section, the website might have Categories such as "Birds" and "Mammals". Within the "Birds" Category, the website might have Articles such as "Parrots" and "Sparrows". In Joomla! versions and up, Categories can contain other Categories. The example above could be created using an "Animal" category, the Categories "Birds" and "Mammals" that are in that category, and the "Parrots" and "Sparrows" Articles in the "Birds" category.

The visible graphical interface features of an application are sometimes referred to as chrome. See Applying custom module chrome for information about how to modify the look of modules (in other words, the module "chrome").

A component is a kind of Joomla! extension. Components are the main functional units of Joomla!; they can be seen as mini-applications. An easy analogy would be that Joomla! is the operating system and the components are desktop applications. They are usually displayed in the center of the main content area of a template (depending on the template).

The database table prefix is a string (a few characters long) prepended to the name of Joomla!'s tables. Using a prefix enables you to run multiple installations of Joomla! using a single database.

An extension is a software package that extends your Joomla! installation in some way. A small selection of extensions is included with the default Joomla! installation but many more are available from the Joomla! Extensions Directory.

jdoc statements are included in every Joomla template and indicate where the output from other parts of Joomla or its extensions should be positioned in the overall web page. A typical jdoc statement looks like this: <jdoc:include type="component" /> See the jdoc statements article for more information.

Languages are perhaps the most basic and critical extension type. Languages are packaged as either a core language pack or an extension language pack. These packages consist of INI files which contain key/value pairs. These key/value pairs provide the translation of static text strings within Joomla! source code. This allows both the Joomla! core and third party components and modules to be internationalised. Core language packs also include an XML meta file describing the language and providing information about the fonts to use for PDF content generation.

Version 1.5 of Joomla! changed the way that third-party Extensions work with the Joomla! core programs. Extensions written for version 1.0 need to be modified in order to use the new 1.5 methodology. To allow for backward compatibility with existing 1.0 Extensions, a Plugin called "System - Legacy" is included with Joomla! 1.5. This Plugin allows many Extensions developed for version 1.0 to work with version 1.5. This Plugin is disabled by default and must be enabled before you can use any Extensions in "Legacy" mode. It can be enabled from the Plugin Manager screen.