Mac/Apple
Wikipeda Link:
http://en.wikipedia.org/wiki/Mac_OS Mac OS X Mac OS X is the newest of Apple Inc.'s Mac OS line of operating systems. Although it is officially designated as simply "version 10" of the Mac OS, it has a history largely independent of the earlier Mac OS releases.
The operating system is the successor to Mac OS 9 and the "classic" Mac OS. Mac OS X also makes use of the BSD code base.
There have been six significant releases of the client version, the most recent being Mac OS X 10.7, referred to as Lion.Mac OS X is also the basis for iOS, (previously iPhone OS) used on Apple's iPhone, iPod Touch, and iPad.
Price: $30.00 (App store:
http://www.apple.com/macosx/)