Desktop environments and Window managers

Linux has been (and probably still is) regarded as an operating system for servers, and less suitable for Desktop use. One feature that directly contradicts this idea (not a Linux specific feature, but missing from e.g. Windows) not found in mainstream OSs, is the ability to choose your desktop environment, which means you have total control over what your desktop looks and behaves like. This means depending on what your chosen environment allows, you can change the looks, behaviour and make-up of the desktop environment, use integrated tools, that work well with the chosen environment, and take full control of your productivity, to a degree you might not have thought possible.