Qubes OS
Qubes OS is a free and open-source, security-oriented operating system for single-user desktop computing. Qubes OS leverages Xen-based virtualization to allow for the creation and management of isolated compartments called qubes.
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Besgnulinux
Besgnulinux is a lightweight, desktop Linux distribution based on Debian's "stable" branch. Using the JWM window manager, it is designed to be fast, lightweight and easy to use, suitable for older and low-specification computers.