X-ray | Drupal.org
X-ray module gives a look at the skeletal structure of a site to help developers and site builders see how things work. X-ray Features A technical summary is added to the help above the main administrative sections. For example, blocks, content types, and menus are summarized on Structure; themes on Appearance; etc. A table of permission titles matched to their permission machine names. A table of most* hooks which Drupal invokes (and when they are invoked) and that are available to be implemented. The function and arguments producing each page you visit, displayed on that page.