Xerox had decided not to produce PARC's PC. Mr Jobs organized a tour of PARC's facility with permission to bring along engineers and take notes. He did get the idea for a GUI OS from Xerox but it was not remotely stollen as some like to suggest.

If I'm remembering history correctly, Mr Wozniak had already designed the hardware side of it; keyboard and mainboard mounted in wood chassis with monitor resting on top and mouse beside.

So, Mac OS was inspired by Xerox research however the PC form factor was not (or was inspired by general industry ideas of the time?).