You can invent your own "meta" tags for your html documents that will convey (you guessed it) meta information between the page and the template.

In this example, we've defined a see also link at the bottom of the navigation bar that may is set from within a page by adding:

  <meta name="see" content="see.html">
  
In addition to effecting the template, any page has access to any of the current data contained in the server for this request and session. Here are the currently available data items that may be used:
namecurrent value