SCRIPT_FILENAME: /home/islam52/public_html/infost440/a3/predefined.php
HTTP_USER_AGENT: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
Predefined variables are special variables that PHP provides automatically. They contain useful information about the server, browser, request, and environment. The $_SERVER variable stores server-related information. SCRIPT_FILENAME shows the path of the current script, while HTTP_USER_AGENT provides information about the browser being used.