Extensible markup language that defines a format that is both human-readable and machine-readable. XML files are used in Joomla for installation files, options, and JForm forms.

A link in the back-end that allow you to see what the front-end would look like while you’re still working in the back-end.

A template is a type of Joomla! extension that changes the way your site looks.

There are two types of templates used by the Joomla! CMS: Front-end Templates and Back-end Templates. The Front-end Template controls the way your website is presented to the user viewing the website's content. The Back-end Template controls the way your website's administrative tasks are presented for controlling management functions by a Joomla! Administrator. These would include common tasks such as: user, menu, article, category, module, component, plugin and template management.

Reference: http://docs.joomla.org/Glossary

It stands for Extensible hypertext markup language and is an application of XML. Most Joomla pages are based on XHTML.

Joomla uses groups as a method of assigning permissions.

Default groups: Public, Guest, Manager, Administrator, Registered, Author, Editor, Publisher, Publisher, Super Users. However, you can create unlimited user-defined Groups.

The highest user level in Joomla. Members of this group have super user permissions throughout the site. If anything can be done in a Joomla installation, the super user can do it.

A “what you see is what you get” editor.

An article that doesn’t belong to any category.

A collection of related articles. Sub-categories start at one organiza- tional level below categories. Since Joomla 1.6, you may have as many levels of sub-categories as you please (called nested categories).

A Joomla module that allows you to “wrap” directly other Web sites for display on your Joomla site at a specific location as determined by the Module Position and the Pages Items section. The web page is inserted as an Inline Frame (also called an Iframe) into the web site layout template.

Template overrides are a way of changing the way Joomla shows something without changing the basic or core Joomla system. A template override is a layout file that is placed in a special subfolder of the template. If found, it will replace the standard layout file for that template.This means that as Joomla is upgraded to new versions you will not have to repeat all the changes you made.

Stands for Structured query language. The language used to create SQL queries to access and manipulate databases. Includes DDL (data-definition language that manages table and index structure) and DML (data manipulation lan- guage, the subset of SQL used to add, update and delete data).

The program that uses client/server models. It provides the communication between the browser on the client device and the server where the website files and database are stored. Joomla works with two leading web servers: Apache and Microsoft IIS (Microsoft's Internet Information Server).

Template style is a feature introduced in Joomla 2.5 that allows users to assign different template styles to individual menu items. By default, Joomla! assigns a template style to all menu items upon installation. A yellow star indicates the default template style in use. A default template style can be partially or completely overridden by assigning different template styles to the desired menu items in order to obtain a different look for their respective pages.

A template style can be assigned to menu items one of two ways.

Template manager Extensions ? Template Manager

Editing a menu item under Menus ? Menu Name ? Menu item

Reference: http://docs.joomla.org/Glossary

A split menu is where different levels of a single menu are displayed in two or more locations on a single web page.

For example, a common requirement is for a menu of top-level items to appear at the top of the page. When one of the items is clicked the user is taken to a page where a secondary menu, say on the left of the page, shows second-level items within the scope of the top-level item.

The menus appear in separate locations on the page, but are related because one shows only top-level items while the other shows second-level items.

This idea can be extended to include menus for third-level items and beyond.

This can be implemented in Joomla using a single multi-level menu then creating more than one menu module each referring to a different level.

Reference: http://docs.joomla.org/Glossary

One of the elements of the model-view-controller design pattern used for Joomla core components. The view is responsible for generating output sent to the browser by the component. The base API class we use for views is called JView.