We’ve been using all of them in virtual machines in System Software class. I’m still not quite sure if anyone actually ever used Windows 1, but Windows 3.1 was as normal as you could get on a PC (of course the Apple Mac was already a whole other ballgame and years ahead – on of their adverts mentioned “Windows 95, Apple Mac 1984”). Windows 95 was terribly exciting. Windows XP made it all work finally. I think it’s been downhill since then.