Its a flag and if its value is set to one we must use the longer version of the variable
| Array Name | Longer version of the name |
| $_POST | $HTTP_POST_VARS |
| $_FILES | $HTTP_POST_FILES |
| $_GET | $HTTP_GET_VARS |
| $_COOKIE | $HTTP_COOKIE_VARS |
| $_ENV | $HTTP_ENV_VARS |
| $_SERVER | $HTTP_SERVER_VARS |
| $_SESSION | $HTTP_SESSION_VARS |
Its not at all a convenient option , so its always better to have the value set to off