PHP is another server-side scripting language that delivers HTML pages to the user 's browser. For an overview of PHP, see http://www.php.net/.
For more information on PHP see PHP Pocket Reference by Rasmus Lerdorf (O'Reilly). Also see Webmaster in a Nutshell by Stephen Spainhour and Robert Eckstein (O'Reilly).
PHP files have a .php , .php3 or .php4 extension. Blocks of PHP code start with <? and end with ?> . Therefore, the PHP.xml file includes the following <tagspec> element that identifies PHP code as string-delimited:
<tagspec tag_name="php" detect_in_attribute="true" start_string="<?" end_string="?>" icon="PHP.gif" icon_width="17" icon_height="15"> </tagspec>