Not all posts in WordPress are posts. This means that the post table stores more data than the regular posts, and these regular posts are but one of the types of data that are stored in that table; there are others. Pages are also a type of post, as post revisions, attachments and —since 3.0— the navigation items. Plugins and themes can add custom post types.
By the Web Warlock, Saturday, 24/Jul/2010 0:03