Understanding CMS technologies

We haven't discussed the technical aspects of CMSs so far. Let's quickly review them here.

Web-based CMSs have a simple three-tier architecture, just like any other web application: Browser → Web Server → Database Server. Internally, different CMSs may have different system designs. However, the overall components and flow still remain the same. Take a look at Joomla!'s architecture in the following figure:

And here's Drupal's execution system flow:

Most CMSs will have similar design, which consists of a few core components, plug-in systems, and template handlers. The flow will be similar too—process templates, permissions, content blocks, and actual content.

Apart from the system architecture similarities, you may have noticed another similarity in top CMSs—the backend technologies that they use. Most are written in PHP with MySQL as the database.