Drupal

ENTERPRISE CMS
An Enterprise CMS (ECM) encompasses the content, documents, details and records related to the organisational processes of a commercial enterprise. The purpose and result is to manage its unstructured information content, with all its diversity of formats and locations.
WEB CMS
A Web CMS (WCM) is designed to simplify the publication of web content to websites or mobile devices by allowing the creation, submission and management of content without prior requiring technical knowledge of any web programming/markup languages i.e. HTML.
WEB GROUP CMS
The Web Group CMS (GMS) is very similar to WCM – the main difference being the fulfillment of some specific requirements that aim to satisfy the needs of groups or small organisations that often have difficulty managing their online image, communicate with their members, plan events, set schedules and assign tasks to internal projects. Typically, these tasks are distributed by different tools and GMS unifies them into one.
COMPONENT CMS
In a Component CMS (CCMS) like drupal, content is stored and managed at the sub-document (or component) level for greater content reuse and convenience.