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Mac OS X

macOS
MacOS wordmark.svg
MacOS Sierra Desktop.png
Screenshot of the latest version of macOS, Sierra (10.12), as of September 2016
Developer Apple
Written in
OS family Macintosh, Unix
Working state Current
Source model Closed source (with open source components)
Initial release March 24, 2001; 15 years ago (2001-03-24)
Latest release 10.12.3 (16D32) (January 23, 2017; 13 days ago (2017-01-23))
Marketing target Personal computing
Available in 34 languages
Update method
Platforms
Kernel type Hybrid (XNU)
Default user interface Graphical (Aqua)
License Commercial software, proprietary software
Preceded by Classic Mac OS
Official website www.apple.com/macos

macOS (pronounced /ˌmækɛs/; previously Mac OS X, then simply OS X) is the current series of Unix-based graphical operating systems developed and marketed by Apple Inc. designed to run on Apple's Macintosh computers, having been preinstalled on all Macs since 2002. Within the market of desktop, laptop and home computers, and by web usage, it is the second most widely used desktop OS after Microsoft Windows.

Launched in 2001, as Mac OS X, the series is the latest in the family of Macintosh operating systems. Mac OS X succeeded the "classic" Mac OS, which was introduced in 1984, and the final release of which was Mac OS 9 in 1999. An initial, early version of the system, Mac OS X Server 1.0, was released in 1999. The first desktop version, Mac OS X 10.0, followed in March 2001. In 2012, Apple rebranded Mac OS X to OS X. Releases were code named after big cats from the original release up until OS X 10.8 Mountain Lion. Beginning in 2013 with OS X 10.9 Mavericks, Apple names macOS releases after landmarks in California. In 2016, Apple rebranded OS X to macOS, adopting the nomenclature that it uses for their other operating systems, iOS, watchOS, and tvOS. The latest version of macOS is macOS 10.12 Sierra, which was publicly released in September 2016.


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