I've never had an opportunity to play much with OSX, but before Windows 3.1 came out I was using Amigas which ran a true preemptive multi-tasking OS based on Unix.
My first encounter with Windows 3.1 was at a friend's house and I asked him if it was multi-tasking. He said it was so I said, format two floppies at the same time to satisfy my curiosity.
He did and they did NOT format at the same time like I was used to seeing on my Amiga. On his Windows 3.1 machine it would hit drive A: then switch to drive B: and so on, but never both at once. It was task switching at best. I used to go to Amiga enthusiasts groups where they would daisy chain 15 floppy drives up and format disks and copy files en mass for everybody.
It was Windows 95 that finally was true multi-tasking, but Windows was still not in the same league as Amigas. At that point in time I had a hardware card for the Amiga that had an SX386 Intel and some RAM where I was running Windows 95 as a task on the Amiga and at full pop speed as if it were on a dedicated machine instead of in a window on my Amiga.
By Windows 7 Microsoft had finally eclipsed the Amiga, but Commodore had been out of business for a good while by then.
Now that I am running Linux, it feels like a continuation of the experience I had when I was on my Amiga and my friends were all running Windows 3.1.
