Kali Linux is a Debian-derived Linux distribution designed for digital forensics and penetration testing. It is maintained and funded by Offensive Security Ltd. It was developed through the rewrite of BackTrack, their previous information security testing Linux distribution based on Knoppix.
Kali Linux has over 600 preinstalled penetration-testing programs, including Armitage (a graphical cyber attack management tool), Nmap (a port scanner), Wireshark (a packet analyzer), John the Ripper password cracker, Aircrack-ng (a software suite for penetration-testing wireless LANs), Burp suite and OWASP ZAP web application security scanners. Kali Linux can run natively when installed on a computer's hard disk, can be booted from a live CD or live USB, or it can run within a virtual machine. It is a supported platform of the Metasploit Project's Metasploit Framework, a tool for developing and executing security exploits.