Mac OS X
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Mac OS X(operating system)
/mak oss ten/ Version 10 of the Macintosh Operating System, based on FreeBSD unlike prevoius versions. Apple released the kernel of Mac OS X Server as "darwin", under an open source license. Mac OS X incldues a code framework called the "Core Foundation" and an "Application Kit" framework for GUI and widgets strongly derived from NEXTSTEP.
Mac OS X(Mac OS 10) The current operating system from Apple for the Mac family. Starting in the fall of 2016, Version 10.12 uses the rebranded "macOS" moniker and not OS X. See macOS and Sierra.
OS X Server was introduced in 1999, and the client version came out in 2001. Based on Unix and featuring an entirely redesigned user interface, OS X was a major departure from the previous OS 9 system. For the first time, the rich set of Unix commands became available to all Mac developers (A/UX was an earlier Unix OS for the Mac but was not widely used).
OS X added protected memory, pre-emptive multitasking, multithreading and symmetric multiprocessing (SMP) to the Mac world. The heart of OS X is the open source, POSIX-compliant Darwin kernel, which includes an enhanced BSD 4.4 operating system and Mach 2.5 microkernel. See HFS.
Prior to Mac OS X 10.5 (Leopard), OS X ran legacy OS 9 and earlier applications via its Classic software, which was a full copy of OS 9 that ran as an OS X process. Classic was not preloaded on new Macs, but was available for installation from the system disks.
In 2006, Apple switched from the PowerPC to the Intel platform, and Classic support was dropped in the Intel version of OS X. However, PowerPC applications could run on Intel Macs via an emulator (see Rosetta).
There have been five programming interfaces (APIs) for writing Mac OS X applications. Cocoa is the native OS X interface, derived from OpenStep. Carbon is used for applications that can run on both OS X and earlier Mac OS machines, and Classic is the API prior to Mac OS X. Programs can also be developed in Java and BSD. See OpenStep and Cocoa.
Mac OS X versions were internally code-named after jungle cats. Starting with Version 10.2 (Jaguar), the animals became the official product name until Version 10.9 (see below). See Rhapsody and Bonjour.
OS X Version Jungle Cat 10.0 2001 Cheetah (code name) 10.1 2001 Puma (code name) 10.2 2002 Jaguar 10.3 2003 Panther 10.4 2005 Tiger 10.5 2007 Leopard 10.6 2009 Snow Leopard 10.7 2011 Lion 10.8 2012 Mountain LionOS X Version Place 10.9 2013 Mavericks 10.10 2014 Yosemite 10.11 2015 El CapitanmacOS Version Place 10.12 2016 Sierra 10.13 2017 High Sierra 10.14 2018 Mojave