There are a wide array of reasons as to why one should use Kali Linux. Let me list down a few of them: As free as it can get - Kali Linux has been and will always be free to use. More tools than you could think of - Kali Linux comes with over 600 different penetration testing and security analytics-related tools. Open-source - Kali, being a member of the Linux family, follows the widely appreciated open-source model. Their development tree is publicly viewable on Git and all of the code is available for your tweaking purposes. Multi-language Support - Although penetration tools tend to be written in English, it has been ensured that Kali includes true multilingual support, allowing more users to operate in their native language and locate the tools they need for the job. Completely customizable - The developers at offensive security understand that not everyone will agree with their design model, so they have made it as easy as possible for the more adventurous user to customize Kali Linux to their liking, all the way down to the kernel. Few of the things you get to learn in this guide are: