I know there's an existing thread asking people what other operating systems they've used, but I can't find it.
No Windows, no Linux, no macOS: is there really a desktop operating system that's worth using outside of the big three? We've set out to answer that question, and while there are no absolute definitive answers here – everyone's use case is different, after all – we've discovered ten distinct examples that fall outside the usual bounds.
There are descendants of UNIX, OS/2, BeOS and DOS, and operating systems which take inspiration from platforms as diverse as AmigaOS and Windows NT. Our list even includes a few true outsiders, independent operating systems built from the ground up which serve mainly to prove just how difficult it is to create an entire functioning OS without a large number of brains working on it.
