Liya Zhu - Assignment 3 - Escape

Example

You are running the file:
/home/liyazhu/public_html/assignment3/predefined.php.

You are viewing this page using:
Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)

This server is running:
Apache.

Explain

PHP has many predefined variables.These allow you to quickly glean important and frequently used information.

Let's look at variable $_SERVER, for example,

$_SERVER['SCRIPT_FILENAME'] variable stores the full path and name of the script being run

$_SERVER['HTTP_USER_AGENT'] variable represents the browser and operating system of the user accessing the script.

$_SERVER['SERVER_SOFTWARE'] variable represents the web application on the server that's running PHP (e.g. Apache, )