Apache/PHP filtering?

IIS supports (for lack of a better term) embedded ASP within HTML pages and still interprets it. Does such a thing exist for PHP and Apache? I've set up the PHP as a module in Apache and would like to do the following (notice the filename has a .html extension): <html> <body> This is a test. <?php echo "This is code within an HTML that does not have a .php extension"; ?> </body> </html> I realize that I could just change all the extensions to PHP where I want to do this, but I'm curious about whether I'm missing something? Thanks in advance RDB