Graham Mowi7 That particular site uses PHP so you cannot use the exact code
But it is basically very simple
The default page contains a set of include functions that use the variable 'func' to include other files into a basic framework you can do it with xt:includes like this
<div class="header"><xt:include file="/headers/{_$func|}" /></div>
<div class="main"><xt:include file="/main/{_$func|}" /></div>
<div class="footer"><xt:include file="/footers/{_$func|}" /></div>
The variable can actually have any name