Using Joomla! as an example, I will briefly explain the structure of a WCMS.
Front End and Back End
A WCMS consists of a front end and a back end. The front end is the website that the visitors and the logged-on users see.
The back end, on the other hand, contains the administration layer of the website for the administrators. Configuration, maintenance, cleaning, the generation of statistics, and new content creation are all done in the back end by authorized people. The back end is at a different URL than the website.
Access Rights
Whenever we talk of management, we talk of the clever administration of existing resources. In a WCMS, user names and group names are assigned to the people involved and each one of them is assigned different access rights. This ranges from a simple registered user through an ‘author’ and ‘editor’ up to the ’super-administrator’, who has full control over the domain. Based on the rights, the website then displays different content; an option is available to edit content directly in the front end, or the user is given the right to work in the back end.
Content
Content can come in all kinds of forms; in the simplest case, it is text. However, content can also be a picture, a link, a piece of music, a snippet from an application like Google Maps or a combination of all of these. To keep an overview of the content, one embeds it in structures, for example, texts of different categories. The categories, of course, are also content that needs to be administered. Newsfeeds have become very popular, since Internet Explorer 7 now has the capability to read RSS feeds and more than 80% of computer users still use this browser. Newsfeeds give you the option of integrating information from other sources. Integration, categorization, rating, mashing, and updating of newsfeed content is becoming more and more important.
Extensions
Components, modules, templates, and plug-ins are all referred to as Extensions. They offer additional functions that are not contained in Joomla!’s core.
Components
Joomla! has to be expandable and should be able to grow with the requirements. Extensions that offer additional functionalities and that usually have their own area in Joomla!’s administration are called components. For example, typical components of recent years are an online shop, a picture gallery, and a newsletter or forum system. Today things like search engine optimization, user rights, multi-page forms, and variable content structures are becoming more and more important.
Components contain the business logic of their site and display content in the ‘main body’ of the website.
Templates
A template is a kind of visual editing pattern that is placed on the top of content. A template defines the colors, character fonts, font sizes, background images, spacing, and partitioning of the page, in other words, everything that has to do with the appearance of a page. A template is made up of at least one HTML file for the structure of the page and one CSS file for the design. It can also have a far more extensive structure in order to prepare Joomla! content for barrier freedom or for a completely different purpose.
Plug-Ins
A plug-in is a piece of programming code that is appended at certain places in the Joomla! framework to change its functionality. Such a plug-in can, for instance, be used inside content text to load the content of a module into the text. Plug-ins are also used in a comprehensive website search in order to integrate additional components. Sometimes plug-ins are used like a macro language in Joomla! Special modules pertaining to components are used to integrate content in the desired form into templates. The Recent News module, for example, delivers the headlines of the last five articles that were placed by the Content component to the template. Another module, for example, determines the number of users that are on-line at the moment and displays the result.
Workflow
By workflow one understands a sequence of operations. The bureaucratic set of three (mark, punch, and file) is an example of a workflow. A recipe for baking a cake is also a workflow. Since several people usually work with CMS content, well-organized workflows are a tremendous help.
In the past, one also referred to work inventories that a certain user has. For example, the editor sees a list of non-published pieces of news, which he or she has to examine for correctness. After examining them, the editor marks the pieces of news as correct and they appear in the work inventory of the publisher. The publisher then decides whether to publish each piece on the front page.
Configuration Settings
Settings that apply to the entire website are specified using the configuration settings. This includes the title text in the browser window, keywords for search engines, switches that permit or forbid logging on to the site or that switch the entire page offline or online, and many other functions.
API
Today an Application Programming Interface (API) has to be provided to be with the times. It has to be possible (and it is) to access Joomla! from other programs and to invoke it remotely to some extent. This opens up entirely new applications that were previously not feasible with Joomla! An API is the most important link between third‑party extension developers and the Joomla! core.
