Phpinfo()

The built-in PHP function, phpinfo(), echos information about the currently running PHP installation. This is a simple way to test that PHP is installed and functioning. It also provides useful information for debugging.

Example of Usage

<?php
phpinfo();
?>

Note: Use of PHP long tags ( <?php ) are recommended for the most compatibility over short tags ( <? ) which require the php.ini setting of short_opentag=On

Resources

PHP Manual: phpinfo