Drupal is a free, Open Source content management system (CMS) to build and maintain websites, online directories, e-commerce stores, intranets and other types of digital content. It can be used by individuals or groups of users and is a useful CMS for developers, marketers and agencies.

function Drupal::url. Generates a URL string for a specific route based on the given parameters. This method is a convenience wrapper for generating URL strings for URLs that have Drupal routes (that is, most pages generated by Drupal) using the \Drupal\Core\Url object.

You can usually tell a drupal site by going to the home page and displaying the page source. In the top section there are numerous references to the typical drupal folders and files. Doing this on this site shows zero indication it is a drupal site.

Robust, Developer-Friendly Platform Often regarded as a “developers' CMS”, Drupal excels in creating complex, scalable websites. Its robust features support sophisticated development and personalization, offering more capabilities than many other CMS platforms.