Because of all the recent news on Valve’s linux and OS X support for Steam and Source, I keep reading that same old misinformation again. So I repeat:
Apple’s OS X is NOT linux!
I’ve written a blog on the confusion of linux, UNIX and other OSes a while ago, but it seems another one is in order. So I will just repeat myself here:
I also see that with regards to MacOS a lot. People seem to think that it is based on linux. Which it isn’t. MacOS has its own kernel, called XNU. The rest of the OS is also not entirely like a linux distribution. Namely, where linux distributions generally are based on the FSF GNU software distribution for the ‘world’, MacOS stems from Darwin, which in turn is based on BSD, and only certain parts are taken from the GNU world (such as the GNU Compiler Suite).
The differences are very small, the software mostly looks the same from the outside, but the origins of Darwin and BSD are different, as is the licensing (obviously). I find it a bit strange that linux seems to have become equivalent to any Unix-like OS, in the minds of a lot of people.
So, linux distributions are named after their kernel, which is the linux kernel. Since OS X does not use this kernel, but its own XNU kernel (from the Darwin project, which is built upon earlier work done by NeXT, the company that Steve Jobs started when he left Apple), that is already a glaring dissimilarity. Another major feature of most linux distributions is that they mainly depend on GNU code (under the GPL license), and the correct way to refer to a linux-based OS as a whole is to refer to it as GNU/linux (yes I’m actually citing Stallman here!). Now, since OS X is mainly based on BSD code (taken from the FreeBSD and NetBSD projects), that is a second glaring dissimilarity. If anything, OS X would be called something like BSD/Darwin/XNU, not GNU/linux.
Please people, try to get it right sometime! I know the linux community is ignorant, but you’re all about openness and freedom of information, right? Well, this information is open and free, and it’s right out there. All you have to do is look! OS X is in no way part of your imaginary linux success story, so don’t spread FUD by claiming otherwise! Wasn’t FUD the reason why you people hate Microsoft, and the reason why you use linux in the first place? (which would be the same reason you accuse Windows users of: you use it because you don’t know anything else, and never bothered to look).
Oh, and by the way:
The ‘Open’ in OpenGL does not refer to open source either (it refers to ‘Open Standard’, which is not quite the same)! Most implementations of OpenGL are closed source, and the OpenGL name is trademarked. Which is why the main open source implementation of OpenGL is called MesaGL, not OpenGL (MesaGL is not licensed to use the OpenGL trademark).