Comment Re:Mac OS X is not founded on FreeBSD (Score 1) 220
NextStep consisted of the Mach microkernel, BSD (probably the 4.3 release, and updated to 4.4 and Net/2 when later available), and some other technologies outside the BSD arena. After Apple purchased it, it probably contained whatever the latest free BSD code was available...4.4 BSD-Lite, probably, since 386BSD was the original BSD port to Intel hardware (from which FreeBSD was derived)/ Darwin was Apple's open source release of their [then] current version of Mac OS X...Cheetah, I think? I played with a copy of OS X server when it was first released in 1998, and found the command-line remarkably similar to FreeBSD 2.x (though I was not an expert and the BSDs have kept many BSD-isms throughout the ages). Apple had probably integrated the latest BSD derivative available for that Mac OS X release. I remember reading about a switch to from FreeBSD 3.x to 5.x in the Panther release notes or somewhere similar, so they had long since switched to FreeBSD from whatever NextStep used by the time Darwin was released.
So, no. Darwin wasn't originally based on FreeBSD. Darwin was the source code based on released version Mac OS X, which was originally based on NextStep/OpenStep, which was based on Mach/BSD, which existed before FreeBSD.
The Apple Darwin kb page linked above is part of Apple's (now-defunct) attempt to drum up interest in Darwin as the core of Mac OS X, but wasn't a fork of 4.4BSD as the AC post above implied.