swa66 - 2:05 pm on Oct 25, 2009 (gmt 0)

Apple OS X is under the graphical hood and above the mach kernel a FreeBSD derivative. FreeBSD is based on the unencumbered BSD 4.4 (just like it's siblings NetBSD and OpenBSD).All of those are heirs of BSD unix dating back to the very beginning of unix. All of these BSD heirs are released under a "BSD" style license that allows nearly everything (except claiming you made it) and don't force anythign on the one changing, selling or distributing it.

Linux is made from scratch to resemble unix. It's license is far more restrictive in that it uses a GPL copyleft.

Licensing alone would prohibit most commercial use of Linux in OSes.

Anyway Microsoft offers Office for Mac OS X.