A few years ago I became interested in operating systems that are positioned off the main stream; in other words: That are not Linux, macOS or Windows but still usable as a desktop OS. And since BSD is so well known, I exclude it from the list of systems I will write about here, too. I've started to write about alternative OSs over two years ago. But I didn't find the time and energy to actually look at much and write about it at that time. I've decided to start anew with this entry and put my reviews, tests and introductions of OSs under the topic top:Software:Alternative Operating Systems. You may ignore everything that I've previously written about this topic.