Installing Kali on a Windows 10 Computer
The linked Tutorial shows you Step-by-Step How to Install Kali 2016.x GNU/Linux Alongside Microsoft Windows 10 OS.
Kali Linux is an Open Source Project that is Maintained and Funded by Offensive Security, a Provider of World-Class information Security Training and Penetration Testing services.
In addition to Kali Linux, Offensive Security also maintains the Exploit Database and the Free Ethical Hacking Course, Metasploit Unleashed.
Kali Installation on Top of Windows 10
Installing Kali Alongside Windows 10