Master
Templating System : Designer Guide : Tag Reference : MasterSummary
The master tag is used to specify the relative or absolute URL of another template to serve as a frame for the current template. The entire contents of the current template are inserted into the master template at a position designated by the slave tag in the master template.
Usage
<master src="master"> <property name="title">My Home Page</property> <p>Welcome to my home page!</p> ...