Browsers don't see PHP scripts?!

Hi, I was unable to see any of the sample PHP scripts from the first pages of the Manual in Netscape under Linux and IE under Win 2000. What's wrong?! Thanks. _______________________________________________________________ <html> <head> <title>Example</title> </head> <body> <B> PHP test </B> <?php echo "Hi, I'm a PHP script!"; ?> <? echo ("this is the simplest, an SGML processing instruction\n"); ?> <?php echo("if you want to serve XML documents, do like this\n"); ?> <script language="php"> echo ("some editors (like FrontPage) don't like processing instructions"); </script> <% echo ("You may optionally use ASP-style tags"); %> <%= $variable; # This is a shortcut for "<%echo .." %> </body> </html>