Qubes OS is an open-source, free, security-oriented operating platform for single-user desktop computing. Qubes OS uses Xen-based virtualization for the creation and management a set of isolated compartments known as qubes. These qubes are virtual machines (VMs) that are used to implement a set of isolated applications for professional or personal projects. They also serve to manage the firewall and network stack. Qubes provides your computer with the security of Xen hypervisor, which is used by many major hosting companies to isolate websites from each other. You can't decide which Linux distribution to use? You still need one Windows program for work? Qubes doesn't limit you to one OS. Qubes integrates Whonix, making anonymous browsing over the Tor network safe and simple.