To help you develop and publish your website, each Acquia Drupal distribution uses a collection of included modules. These modules, provided by Acquia and the Drupal community (and by Drupal itself), provide a base level of integrated features that you can use as you develop your website.
Drupal core modules
Regardless of the version of Drupal that it's based on, Acquia Drupal contains a group of Drupal core modules that can be enabled or disabled, but not uninstalled. These modules provide the base level of functionality for your website, including the areas of content creation, display, and website administration.