What does publication mean?

Each individual node has an attribute associated with it which determines whether it is rendered as a part of basic site operations, i.e. used to populate the site's home page, list of coming attractions, or any other block. Nodes which are not yet published do not appear on any of these blocks, but can still be accessed by the user originally creating the content (or by an administrator) directly by node number. This allows such nodes to subsequently be editted and have this 'published' attribute enabled, so that other users (and potentially guests) can be given access to this content.