Is Windows becoming more like Unix, or moving away from it?
This was my answer on Quora. I moved it here.
Why not both?
Almost all of fundamental differences between Windows NT and Unix came from the requirements of backwards compatibility with existing software such as MS-DOS , OS/2 and Windows 3.1 rather than philosophical disagreements. Of course, the architect of Windows NT came from VMS team hence its design contained similar elements but primary constraint was always supporting existing application and development base, not because Microsoft didn’t like Unix. Microsoft even had its own Unix in the 80′s, called Xenix.
Windows NT was designed to support an entirely different ecosystem than what Unix variants set out to do. There is no inherent technical limitation for Windows not become more-Unixy, or less-Unixy depending on the needs of customers. Actually Windows NT came with a POSIX compatibility subsystem since its first day. Today, it can run Linux applications natively. Did it become more like Unix? No.
Similarly, Unix can run Windows applications using an emulation layer. Modern Unix interfaces have a “start menu” which was a Windows hallmark. Unix, over the years, digressed from “everything is a process” and “everything is a file” philosophy to “threads are good too” and “device trees are also nice” which were common themes on a Windows system. Did Unix become more like Windows? No.
Meanwhile Windows innovated greatly on graphical subsystem along with DirectX and WDDM, invented an object-based shell, added built-in malware protections. So did it stray away from Unix with those? I don’t think so. I think that’s just business rolling.
There is not a magical tint on Unix or Windows that makes one the ultimate form of a perfect operating system design. On a similar note, a better operating system design isn’t necessarily a successful one. They come with many good ideas that all can be improved. I also find great ideas in now dead operating systems, such as AmigaOS and BeOS. We should strive for making our lives better rather than sticking to cliques.