From my experience in CS at NU, either works fine, but more people have Macs. I got a Mac for college and definitely prefer it to all Windows computers I’ve used in the past. For CS, it’s also more convenient, as OSX is UNIX-based, so once you go on to higher level programming, you’ll have an easier time navigating NU’s UNIX sever. When it comes to writing your code, Xcode is also fantastic and Mac-only, certainly better than Window’s Visual Studio.