Debian
The Debian Project is an association of individuals who have made common cause to create a free operating system. This operating system is called Debian.
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Parrot
Parrot (formerly Parrot Security OS) is a Debian-based, security-oriented distribution featuring a collection of utilities designed for penetration testing, computer forensics, reverse engineering, hacking, privacy, anonymity and cryptography. The product, developed by Frozenbox, comes with MATE as the default desktop environment.