If you visit the create content link you'll see multiple content types configured for your use. In Drupal terms, each page in this guide, story or page is considered a basic content type known as a node. Thus, each of the various content types are particular types of nodes with specific functions and display characteristics:

• Stories are posts which appear on the default home page of a Drupal site, akin to a community weblog or Slashdot-like site where all site members can post. Or, the regular site users can be denied the ability to post to the front page using stories, allowing the site administrators to use the front page as an announcement board.
• Each individual user on the site can have their own blog page. An aggregate of all recent blog posts from all users is available through the Blogs link in the navigation header.
• Forums are much like any other threaded discussion forum where users can post to forum areas created by an administrator.
• Books, in this distribution, are used for the Drupal Site Configuration Guide, but can also be alternatively used for collborative projects (not covered within this documentation).
• Static pages are a way for a site administrator to create pages which are not included in one of the other node displays and could be used instead of the Books for additional resource pages.

See also the administration help in the Drupal handbook for nodes, stories, books, forums, blogs and pages