Example 1: $_SERVER['SERVER_NAME']

The server's host name is: singh275.soisweb.uwm.edu

Example 2: $_SERVER['PHP_SELF']

The current script path is: /infost440/a3/predefined.php

Explanation

Predefined variables are built in arrays that PHP automatically populates with information about the server, request, and environment. They are always available in every scope. For example, \$_SERVER contains data such as the server name, software, and current script path, which is useful for debugging, logging, or creating dynamic links.