The Templating system simplifies the process of unifying the look-and-feel of a website by supporting nested templates. This nesting structure can be as deep as the site designer feels is necessary.

• <master> This tag specifies a "wrapper" template for the current template. If the name's not specified, a default master (set by an acs-subsite parameter) is used.

• <slave> Used within a master template to specify where the "wrapped" or "inner" template should appear.

As a practical example, look at the index page returned after a standard OpenACS install. The top header bar (with the login/logout links, system name, etc) comes from the site master template, which "wraps" all content within the site. Master templates can also specify CSS stylesheets, which can be used to change the appearance of fonts and the output of HTML tags throughout the sites (the development of standard .css classes and their use throughout the toolkit is currently underway).