Here is a snippet of PHP that can be used to import content (ie just the bit that does the stuff, not a whole page). The presumption is that there is a folder called pages, in which there are some .inc files containing the main page content of some web pages. These files will not have the head or body tags. Just like in the previous example, the top and bottom of the document will be imported from the templates folder.
$page = "pages/".$_GET['page'].".inc";
// Output some hyperlinks with query string of page name.
Set up half a dozen basic pages and save them in your pages folder. Write some hyperlinks where there is a query string for the variable page. The .inc part of the filename will not be used in the URL.