In fairness to all concerned, the MacOS to MacOS X transition was brilliantly executed. These days we take VMs for granted, but back then it was a novel idea to run MacOS 8 as a process inside of MacOS X (the "blue box"). For most users it was seamless.

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bombcar 2 hours ago | parent [-]

Microsoft had done something similar (twice!) but Apple polished the living daylights out of it.

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wat10000 2 hours ago | parent [-]

Apple did it before as well. A/UX ran System 7 in a UNIX process. That was a really niche system, though.

	▲	bombcar an hour ago \| parent [-]
		That and XENIX are really interesting “what might have beens”.