Originally Posted by Nekoniaow
And it's a good example of OS transition btw: the original System 9 of the Mac was outdated, slow, buggy, not multitasking, with horrendous limitations imposed on programmers and they transitioned into OS X (X = 10, for System 10) which was actually a completely different OS, a NetBsd/Unix to be precise with temporary backward compatibility.
It is actually a FreeBSD userland running on top of a Mach kernel. Of course both of them are bastardised so that they don't perform as well as they should. That OS is nothing more than a hack and I can't believe people pay thousands of dollars for an Apple when the OS runs just fine on a generic PC.