Hello,
This is my first tutorial at astahost. It covers how to make a simple template system, which I use in some of my software.
To start, we need a page that will be the template itself. For this tutorial, below is a very simple one:

Save this as template.html

Next, the php, also very simple:

You'll notice the variables $content contains the content of the page you wish to appear. This coding is simple and can easily be expanded on, for instance, you could use GET to have multiple pages, or have sidebars and add extra variables for them. It's simple coding, but it's not bad either.