To do what he suggests, your server must have <A href="http://www.php.net">PHP</A> installed. If yours does, you only need to change your extension to .php and it should render. If you are running this server on your own Mac OS X machine, download the <A href="http://www.entropy.ch">entropy.ch package</A> and install it!
Also may want to look into <A href="http://httpd.apache.org/docs/howto/ssi.html">server-side includes</A> <!--#include virtual="/page.html"-->