Qubes is a Fedora-based Linux OS running on Xen, a bare-metal hypervisor. Qubes’ most interesting feature is the ability to run one or more security domains. The idea is to provide a more secure OS in which it’s highly difficult for one exploited app to impact apps or environments. In practice, strong security domain isolation is very difficult to achieve in practice. The stricter the security domain, the less usable the feature, the more secure the feature. In real-life, usable operating systems, applications running on the same computer have to interact all the time.”]
Source: https://www.csoonline.com/article/2609492/should-you-switch-to-a-supersecure-operating-system-.html