ReactOS is an open source clone of Windows NT based Operating Systems. It is only in the alpha stage of development but in the future we will be able to dump Windows from our computers and use ReactOS.
Despite decades in development, ReactOS is still considered alpha software that’s recommended for testing and evaluation purposes. You probably won’t want to replace your primary operating system with ReactOS anytime soon. (...) But fans of open source software, not to mention fans of the classic Windows experience who have been less-than-thrilled with the direction Microsoft has taken in recent years might want to keep an eye on this project. We might of course, switch to Linux first.