Here, then, for anyone considering running Windows 10 on a Mac, is an explanation of the three different ways to run Windows and why you might, or might not, want to do each. And just to confuse matters further, you can get the best(ish) of both worlds and run your Boot Camp Windows installation using Parallels, without having to reboot the entire system. Why have I got two lots of Windows 10 on the MacBook? Because a Boot Camp installation and a virtual Windows 10 running in Parallels Desktop have different strengths and weaknesses, which make it worth the extra storage space sacrifice. That noise you can hear is Steve Jobs spinning in his grave at 7,200rpm. There are three operating system instances running on my Mac – two of them are Windows 10.