Joomla Glossary - C - Definitions Beginning with C

Continuing our series of 'articles' examining the terminology and jargon that a novice Joomla user is going to have to come to terms with. As with all articles in this series we have broken the terms down into two groups: those terms that are Joomla specific and those more general IT terms that our new user is likely to have to come to terms with.  I hope that we are now well on the way to building the most comprehensive glossary of Joomla as we continue with the letter 'C' and any related terms out there. If you think we have missed anything feel free to drop us a line.

Joomla terminology:

These are the Joomla specific technical terms that we have identified and that we hope will help the new Joomla website operator.

Cascading Style Sheets (CSS)

Cascading Style Sheets (CSS) separate the presentational styles of a web page from 'structure' and the 'content'.
Examples of 'presentational' elements include fonts, margins, colours and background images.
Examples of document structure include Major headings, sub headings, paragraphs and spans (short stretches within paragraphs for example).
The 'content' is your words, sentences, paragraphs, etc.

By separating these three 'layers' we make maintenance and updating easier.  We can also specify them in one place for the whole site - and have each and every page load the same set of style instructions, with the styles cascading throughout the page or an entire site. Cascading Style Sheets are contained in a file with a '.css' file suffix.


It is bad practice to have any styling 'hard-coded' to any element of a page, for example <font size="3" face="verdana" color="red">Some text</font>.


Categories are sub-divisions within 'Sections'.  They are collections of related Content Items;  for example, if you had a 'Section' called Cars you could have Categories such as Ford, Vauxhall and Fiat. Within the 'Ford' category you could have articles on 'Model T', 'Sierra', 'Escort', 'Cortina', etc.

Sections contain Categories which in turn contain articles (also known as Content Items) (see also: 'Article and Section').

Category Name

The longer of two name related 'fields' when creating or editing categories. It is intended for display in headings in the main part of the page (where there is usually generous space available).

Category Title

The shorter of the two 'fields' identifying a category. It is displayed in menus which typically are in narrow columns and where space is at a premium.

Check Out (an item)

This is important - confuses newcomers - so is deserving of a little more attention than most of our entries.

Joomla is a multi-user solution. In the past one person had your website on their PC which they edited in Adobe DreamWeaver or another similar text editor, when complete they re-upload the document to your web space. Joomla is different - very very different. With Joomla multiple people can edit the site simultaneously. This is a real strength - but a system is needed to stop two or more people editing the same article at the same time.

Imagine two people 'User A' and 'User B'. 'A' opens an article and spend 30 minutes editing it. After 10 minutes user 'B' opens the same article - in its initial state because 'A' hasn't save his work yet. 'User A' saves his updated article with many additions and edits. 'User B' was only making a few spelling of grammar corrections. If 'User B' saved his work after 'User A' all of those changes made by 'User A' would be lost as 'B' was working from the original.

Well - relax - Joomla has a system to prevent this. When a user starts to edit an article it is marked in the database as being 'in use'. It is said to be 'checked out' - the terminology derives from real world filing systems where a user removes a file from a filing cabinet and leaves a record card stating where the file has gone and why it was removed and who has it.  When the update is complete and the user has saved his updated work the article is 'checked in' making it available for others to use.  Joomla marks articles that are 'checked out' for editing with a padlock.


If an article is 'checked out' for editing and a user loses his internet connection or his computer crashes or with older versions of Joomla the session expires - the article is never saved. Joomla loses track and thinks it is still being edited.  This leaves the article locked (with a padlock in the admin interface) and leaves no-one able to edit the file.

Relax - don't panic - Joomla has two functions to help.  Logged in users with editing rights can 'check in' articles marked as being checked out to them and thus release them for editing.  The function, is available from the public site (Front-end) for in the 'Users Menu'. Global check-in allows a system administrator to do a similar thing for everything across the site (see also 'Global Check-in').

Client-side Scripting

Computer programming on the web which is executed (runs) client-side (on the user's machine), usually in the user's web browser, instead of server-side (on the web server). This is an increasingly important part of the Dynamic HTML (DHTML) concept (commonly - though incorrectly - known as AJAX or Web 2.0), enabling web pages to be scripted and to show different and changing content depending on user actions without reloading the entire page (see also 'Server-side Scripting').


This is an acronym for Components, Modules, and Templates - this is used as the generic 'catch all' term for all Joomla add-ons


These are applications that are usually displayed in the centre of the main content area of a template. The actually display position depends to some extent on the design of the template in use but it will be the 'main' display area of the page. Components make up much of Joomla's functionality. Core components include Banners, Contact, News Feeds, Polls, and Web Links. Many members of the Joomla community produce their own components and distribute them for use by others - sometimes these are free and sometimes they are commercial releases, either way they enhance the Joomla community and the Joomla CMS.  Many of these 'third party' Joomla Components  are freely available to download from the Joomla Extensions Directory and a number of other web sites (see also 'Modules, Mambots and Templates').

* Editor's note (George): My colleague 'Dean' worked on the early prototype of the Joomla Extensions Directory.

Configuration File

The configuration.php file is a special file found in the root directory of your Joomla installation (the main folder where you installed Joomla - the one with the index.php file).  It contains special settings that affect the whole of your Joomla site and its operation including the settings required to communicate with the MySQL database and to help locate other files on the system (file and folder paths).

Contact Forms

A core component of Joomla - contact forms are a way for you to allow visitors to your site to communicate with you without having to publish your e-mail address on the site. It is no longer feasible to publish e-mail addresses because of spam bots which harvest e-mail addresses to bombard you with junk e-mail.

Content Item

A 'document' within the Joomla! hierarchy, which may be associated with a particular Section/Category combination (or may be a Static Content Item that is not associated with a Section/Category combination); usually displayed in the main body of your page. Within the Content hierarchy, Section is the top level and is a container for Categories. Category is the next level and is a container for the third level, Content Items.

Content Management System (CMS)

Well, if you are using Joomla already and you don't know this one you haven't been paying attention. If you have landed here as the result of a search of the web then welcome - we are discussing terminology surround Joomla the Open Source Content Management System which is software that enables you to dynamically manage a web site through a web browser - enabling collaboration and distributed working.

A CMS also separates out content (the words of the site) from the presentation making it easy to change the look and feel of a whole website almost at the press of a button.


Familiar term (unofficially) used to describe the team at the centre of Joomla.


The term 'core' also describes the Joomla code distributed in a zip or tar file that contains the official standard Joomla installation. This can be downloaded from the Joomla Code website. The Joomla 'Core' is distinct from the 'add-ons' (extensions or CMTs) developed by third party developers. The 'core' distribution does in fact contain some basic functionality that is peripheral to the basic installation.


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