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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Q4OS
Q4OS is a Debian-based desktop Linux distribution offering a choice of a classic-style user interface (Trinity) and a modern desktop environment (KDE Plasma). The project also develops various utilities, such as Desktop Profiler and Software Center, as well as installers for third-party applications.