Kali Linux is a Debian-based Linux distribution geared towards various information security tasks, such as Penetration Testing, Security Research, Computer Forensics, and Reverse Engineering.

● More than 600 penetration testing tools included: After reviewing every tool included in BackTrack, we eliminated many tools that either did not work or duplicated other tools that provided the same or similar functionality. Details on what’s included are on the Kali Tools site.
● Free (as in beer) and always will be: Kali Linux, like BackTrack, is completely free of charge and always will be. You will never, ever have to pay for Kali Linux.
● Open source Git tree: We are committed to the open-source development model, and our development tree is available for all to see. The source code that goes into Kali Linux is available for anyone who wants to tweak or rebuild packages to suit their specific needs.
● FHS compliant: Kali adheres to the Filesystem Hierarchy Standard, allowing Linux users to locate binaries, support files, libraries, etc., easily.
● Wide-ranging wireless device support: A regular sticking point with Linux distributions has been supported for wireless interfaces. We have built Kali Linux to support as many wireless devices as possible, allowing it to run properly on a wide variety of hardware and make it compatible with numerous USBs and other wireless devices.
● Custom kernel, patched for injection: As penetration testers, the development team often needs to do wireless assessments, so our kernel has the latest injection patches included.
● Developed in a secure environment: The Kali Linux team comprises a small group of individuals who are the only ones trusted to commit packages and interact with the repositories, all of which is done using multiple secure protocols.

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