I think what you mean is how pages like Amazon use dynamic content without even using html pages, or how some sites have dynamic content using .html pages.
The vast majority of them just edit their Apache config file so that .htm and .html files are parsed with whatever engine they use (PHP in this case).
That way the user sees something like "index.html", but what they are really seing is a PHP, ASP, Python, Perl, JSP, whatever, type of file.
This way no one knows what you use on your pages.
It has it's uses, I suppose.