Kali Linux is the world’s most popular offensive-security-optimized Linux distro. Based on Debian Testing, Kali includes more than 300 security tools, including Metasploit, Nmap, and Aircrack-ng. New Kali users might best start by installing kali-linux-default and kali tools-top10. Kali is not meant for use as a daily default operating system for checking your email or web browsing or sharing cat gifs on the Book of Faces.”]
Source: https://www.csoonline.com/article/3528191/kali-linux-explained-a-pentester-s-toolkit.html