This document discusses penetration testing using Kali Linux. It introduces Kali Linux as a Debian-based Linux distribution for penetration testing and security auditing. It describes penetration testing as simulating attacks on systems to identify vulnerabilities. The document then outlines the methodology for penetration testing using Kali Linux, including information gathering, scanning, exploitation, and post-exploitation maintenance of access. It concludes that Kali Linux is a useful free tool for penetration testers to identify security issues.