BSD UNIX with an eye-candy interface, partly developed by Apple, Inc. The internals of the OS (i.e. the GNU Mach Kernel, the X-Windows System, the shells, the command-line binaries and scripts, etc.) were developed in part by the opensource community, whereas Apple, Inc. developed the high-level APIs and the GUI (both are proprietary).
Mac OS X is a good example of what can happen to any *NIX OS if given enough corporate sponsorship (or if it surrenders its licencing to a corporation).
by Judecn August 9, 2006
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A small program considered by some to be an operating system created by Apple Inc.

Mac OS X is an evolution of Mac OS, which was first released on the original Macintosh on January 24, 1984. It has been "updated" yearly since its release, always accompanied by "updates" to existing computer models that consist of one gimmick and .1 gigahertz more processing power. No one knows anything else about the operating system, due to Apple's extreme secrecy

The only way to interact with OS X is with the visual interface, and the user is prohibited from doing anything besides surfing the web and using iTunes.

Back End
No one knows how Mac OS X works. No one. The last person who knew how the code works was Steve Jobs. "Updates" to the operating system consist of changing the images on the operating to make it look more modern.

OS X can only function on Apple-proprietary hardware that has not been updated since 1986. To make smaller computers, Apple pays other companies to take existing hardware and fit it into a smaller form factor, since they themselves do not know how it works. Apple also requests that every piece of hardware be manufactured on one computer chip, to make repairs as expensive as possible.
Person 1: My computer runs on Mac OS X.
Person 2: What do you use your computer for?
Person 1: Visiting Apple's site to buy a new computer and iPhone every year.
Person 2: Nothing else?
Person 1: Nope.
by DrumpfForPOTUS March 12, 2016
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1. That treehouse is a bit Mac OS X.
2. Calm down you bipolar bitch. You can be so Mac OS X sometimes.
by Jeff R W December 12, 2007
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An awesome operating sytem that is the best ever compiled.
For all the haters out there that say apple computers suck they are just mad cuz they dont got one and they got their shitty x86 machines.
Yeah windows is the best i love my blue screen of death!!!!!!!
but mac os x is gay cuz it works properly
by yeahapplesbetter September 25, 2006
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1) A version of the UNIX operating system with Apple's Aqua GUI on top of it.

2) Proof that the people at Apple couldn't hack it at creating their own OS (evidenced by the supreme shittyness of OS 9 and earlier versions, which were inferior even to Windows 95), so they desperately turned to the powerful and respected UNIX to be their saving grace.

3) Oh, and they couldn't hack it with their own chips either, so they went and switched to the same Intel chips that consistently gave PC's the edge in performance for years.

4) An OS that is supposedly safer than Windows... my foot. Mr. Proud to own a mac 's passionate little flame message does little to refute what was said earlier. The bottom line is that Macintoshes make up some 2% of the personal computer market share, so it's a matter of logistics rather than security. And don't give me that root password crap. Any computer can be infected if someone puts enough effort into it. And here's some breaking news for you all: Systematic, a leading computer security provider, reports that Mac OS X is actually less secure than Windows XP. Yeah. That's right.
Face it Mac zealots, you know these to be true. Frankly, I pity you guys for wasting all that money on a product that costs more, runs much less software, is oversimplified, and requires you to spend a lot of money time and again whenever a new version comes out. You have to at least give Microsoft some credit for releasing service packs FOR FREE.

And, it's hilarious how you fanboys all preach the supposed greatness of Apple when they had to turn to outside technologies to make the holy Mac OS X.
by no7orious December 24, 2007
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I used to have Mac OS X as the theme of Windows XP. Now that I’m using Windows 7 and it’s not needed anymore.
by PartTimeBigCat May 25, 2012
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An overpriced Operating system that is based off FreeBSD. Mac users are uncomfortable with the fact of taking care of computers and so they continually bash windows for the usual crashes, virues and the likes, even though, to most compitent PC users, these are hard to come by unless you use a buggy program or look at excessive amounts of porn.

Saying Mac OS X is safe because its unix based very retarded. Why? Solaris 10 is secure and Unix based. Plus IT'S FREE, so if you wanted a secure OS, Solaris already has a 1-up on OS X.

Regaurding the retarded poster about shitty x86 machines, stfu. x86 is the 32-bit instruction set that is put on ALL modern processors, along with the 64-bit set.

The only reason for ever using Mac OS is well, there isn't one unless your a professional graphic art designer. Both Windows and linux have very good software for audio, photo and video editing and they have games. Plus, they are compatible with almost all PC hardware with Linux being also avalable for the nintendo ds that uses the ARM 9 & 7 processors.

Son now that Linux and Windows are able to suit most PC users, why would anyone use a Mac? They have nothing special about them. Nothing. Not one dam thing. I bet no one can list five reasons of why I should use Mac OS X instead of Windows XP (don't say it doesn't get viruses or spyware/adware or it don't crash, cause neither does my XP rig).
My Mac OS X rig is very secure.

So is Linux, plus its free.

by qblasphemy September 7, 2008
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