A CMS is a fair bit more complicated than a simple web server, but you will need to know only the basics to use Joomla effectively. If you understand the general process that Joomla uses to retrieve content, format it, and return it to the requesting web browser, you will be able to see how you can configure the Joomla system to present content in a manner that best suits your needs.
presents a block diagram of a simple web server. Interaction begins when a web browser requests a page of the web server. The web server retrieves the HTML code from the requested static HTML file (e.g. http://www.joomblaster.com/index.html) and returns it to the browser. The HTML file is called a static web page because the page returned to the browser is exactly the content contained in the file stored on the server—nothing more, nothing less. That’s about as simple as it gets.
Now let’s take a look at the process executed by a request to the Joomla CMS, as shown in Figure 1-4. The web browser requests a page of the web server. Although the address of the page requested in the browser’s address bar may appear similar to the request for a simple HTML page, it actually activates a whole processing system. The request causes a part of Joomla to load into the web server and begin executing on the server’s PHP engine. Joomla analyzes the request to determine what content is requested, and then the Joomla system opens a connection to a database server and requests the specified article from the database.
Once the article contents are retrieved, Joomla formats the article using the style selected as the user template. Joomla creates the HTML display content and sends it back to the browser, where it appears to the user in the same form as if a static HTML file was retrieved.
A CMS will dynamically feed content that has been retrieved from a database and formatted through one of the site templates to the web browser. Because the article content is stored as data, the presentation can be changed by simply altering the Joomla template. If you want an entirely new look for your web site, you can select a different template, and instantly a visitor to your site would see the original content in a completely new presentation style.
