Joomla Help Screens

The Joomla! Glossary is helpful for explaining common terms used in Joomla! tutorials, help screens and advanced documentation.

Access Control List¶

Alias¶

Anchor¶

An anchor is created using the <a> tag in HTML. An anchor allows you to place a bookmark inside an HTML page. In Joomla!, you can place an anchor inside an article (for example, using the TinyMCE editor). This lets you create a link that will go directly to that point in the article.

The HTML source code for an anchor looks like the following:

<a name="my_anchor" title="My Anchor"></a>

You can link to an anchor from within the same page using the HTML code

<a href="#my_anchor" ></a>

Clicking that link will take you directly to the location of the anchor tag.

You can link to an anchor in a different page by appending "#" plus the anchor name to the end of the URL. In the example above, if the URL for the article was http://www.mysite.com/my_article.html, then you could link directly to the anchor in that page with the URL http://www.mysite.com/my_article.html#my_anchor.

Article¶

Cascading Style Sheet (CSS)¶

A Cascading Style Sheet or CSS is used to control the presentation of an XHTML page. For example, a CSS file will often control the font, margins, color, background graphics, and other aspects of a web page's appearance. CSS allows you to separate the content of an XHTML page from it's appearance. In Joomla!, CSS files (for example, template.css) are normally part of the template.

See also: Template, Page Class Suffix, Module Class Suffix

Category¶

Every part of Joomla! powered web site or any CMS type of web site needs a method to display and store its content logically. The usual method is by categories and subcategories. Joomla! allows for multiple ways to display and use content controlled by categorisation. Some of the content types which have categorisation are Articles (the main content of web pages), Banners and Contacts.

A category named Uncategorised is the default category assigned to most content types. The Uncategorised category is not descriptive and should be used on as needed basis for content types which do not fall under a specific category.

When creating and assigning categories, you should have a planned structure. As an example, this is one way to categorise several articles on birds:

• Create two top level article categories named Animals and Plants.
• Under the Animals category, create sub categories named Birds and Mammals.
• Under the *Birds sub category, create categories entitled Hawks, Parrots and *Sparrows. This is the resulting category structure

- Animals
  - Birds
    - Hawks
    - Parrots
    - Sparrows
  - Mammals

Now you can create multiple articles in the Hawk, Parrot and Sparrow sub categories using the different genus or common names of the specific types of these birds.

Chrome¶

The visible graphical interface features of an application are sometimes referred to as chrome.

Component¶

Core¶

The word core in Joomla! pertains to the distributed files which are needed to create and administrate a Joomla CMS powered web site. The Joomla core contains all of the necessary functionality to create and manage a new web site quickly and easily.

Database Table Prefix¶

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

The database table prefix can be set during installation. Changing it later is possible, but requires access to the database through a non-Joomla medium or a Joomla Extension such as Akeeba Admin Tools and will cause some downtime.

Extension developers need to use the string #__ to represent the prefix. This will be replaced by the real prefix at runtime.

Extension¶

LDAP¶

Language¶

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 to 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.

Menu¶

In Joomla!, a Menu is a modules containing a set of menu items used for navigation. Each menu item defines a URL to a page on the site. It holds settings that control the display of page content and style.

Model-View-Controller¶

Joomla makes extensive use of the Model-View-Controller design pattern.

When Joomla is started to process a request from a user, such as a GET for a particular page, or a POST containing form data, one of the first things that Joomla does is to analyse the URL to determine which component will be responsible for processing the request, and hand control over to that component.

If the component has been designed according to the MVC pattern, it will pass control to the controller. The controller is responsible for analysing the request and determining which model(s) will be needed to satisfy the request, and which view should be used to return the results back to the user.

The model encapsulates the data used by the component. In most cases this data will come from a database, either the Joomla database, or some external database, but it is also possible for the model to obtain data from other sources, such as via a web services API running on another server. The model is also responsible for updating the database where appropriate. The purpose of the model is to isolate the controller and view from the details of how data is obtained or amended.

The view is responsible for generating the output that gets sent to the browser by the component. It calls on the model for any information it needs and formats it appropriately. For example, a list of data items pulled from the model could be wrapped into an HTML table by the view.

Since Joomla is designed to be highly modular, the output from the component is generally only part of the complete web page that the user will ultimately see. Once the view has generated the output, the component hands control back to the Joomla framework which then loads and executes the template. The template combines the output from the component, and any modules that are active on the current page, so that it can be delivered to the browser as a single page.

To provide additional power and flexibility to web designers, who may only be concerned with creating new designs rather than manipulating the underlying code, Joomla splits the traditional view into a separate view and layout. The view pulls data from the model, as in a traditional MVC pattern, but then simply makes that data available to the layout, which is responsible for formatting the data for presentation to the user. The advantage of having this split is that the Joomla template system provides a simple mechanism for layouts to be overridden in the template. These layout overrides (often called "template overrides" because they form part of the template, although actually it is the layout that is being overridden) are bundled with the template and give the template designer complete control over all the output from the Joomla core and any installed third-party extensions that comply with the MVC design pattern.

Module¶

Module Class Suffix¶

A Module Class Suffix is a parameter used in modules to add a new CSS class to a module. It is used in conjunction with styles defined in a user.css file to change the standard appearance of a module.

The new class name may be used to add any desired styling to the module without needing to re-create all of the existing CSS code. Note that, if you create a new class name, make sure it has a unique name and doesn't conflict with any existing class names.

Module Position¶

Module chrome¶

PHP¶

PHP is a computer scripting language designed for creating dynamic web pages. PHP is widely-used for web development and can be embedded into HTML. It generally runs on a web server, taking PHP code as its input and creating web pages as output. Joomla! is primarily written using the PHP language.

Page Class Suffix¶

A Page Class Suffix is a parameter used in content menu items to add a new CSS class to the page layout. It is used in conjunction with styles defined in a user.css file to change the standard appearance of a module.

The new class name may be used to add any desired styling to the page without needing to re-create all of the existing CSS code. Note that, if you create a new class name, make sure it has a unique name and doesn't conflict with any existing class names.

Patch¶

Plugin¶

Search Engine Friendly URLs¶

Search engine friendly URLs is a term commonly abbreviated as SEF URLs or SEF for short. Normal Joomla! URLs look something like this:

http://www.yoursite.org/index.php?option=com_content&view=section&id=3&Itemid=41

You can optionally have URLs display to look like static HTML pages like this:

http://www.yoursite.org/faq.html

There are built-in options for generating SEF URLs. These are enabled in the SEO Settings (Search Engine Optimisation) in the Site tab of the Global Configuration page. There are also third-party extensions that create SEF URLs for Joomla!.

Split menus¶

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.

Template¶

A template is a type of Joomla! extension that controls page appearance.

• A Site template controls the public appearance of the site content.
• An Administrator template controls the appearance of the site as for administrative tasks such as: user, menu, article, category, module, component, plugin and template management.

Template style¶

Upgrade Package¶

An Upgrade Package in Joomla! is a package of files that contain the files that have changed between Joomla! versions. When this archive is unpacked, it replaces the old version of the modified files with the new version. For example, if fifty files were changed between version 5.1 and 5.2, the upgrade package would contain these fifty files and instructions on how to execute the upgrade. Sometimes this includes database updates and removal of files no longer used.