View source for MacOS

{{Use mdy dates|date=July 2015}}
{{About|the current Apple operating system for Mac computers|pre-2001 versions|Classic Mac OS}}
{{Redirect2|OSX|OS X}}
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{{lowercase title}}
{{Infobox OS
| name                = macOS
| logo                = MacOS wordmark (2017).svg
| logo size           = 100px
| screenshot          = MacOS High Sierra Desktop.png
| screenshot_size = 300px
| caption             = Screenshot of the macOS High Sierra desktop
| developer           = [[Apple Inc.|Apple]]
| family              = [[Macintosh operating systems|Macintosh]], [[Unix]]
| released            = {{Start date and age|2001|03|24}}
| language count      = 34
| language            = As of macOS Sierra: Arabic, Catalan, Croatian, Chinese (Simplified), Chinese (Traditional), Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hebrew, Hungarian, Indonesian, Italian, Japanese, Korean, Malay, Norwegian, Polish, Portuguese (Brazil), Portuguese (Portugal), Romanian, Russian, Slovak, Spanish (Mexico), Spanish (Spain), Swedish, Thai, Turkish, Ukrainian, Vietnamese
| language footnote   = <ref name="macoslanguages">{{cite web|url=https://www.apple.com/macos/how-to-upgrade/|title=macOS – How to Upgrade – Apple|publisher=[[Apple Inc.|Apple]]|accessdate=September 28, 2016}}</ref>
| ui                  = [[Graphical User Interface|Graphical]] {{small|([[Aqua (user interface)|Aqua]])}}
| license             = [[Commercial software]], [[proprietary software]]
| website             = {{URL|https://www.apple.com/macos}}
| screenshot size     = 320px
| supported_platforms = {{plain list|
* [[x86-64]] {{small|([[Mac OS X Tiger|10.4.7]]+)}}
* [[IA-32]] {{small|([[Mac OS X Tiger|10.4.4]]–[[Mac OS X Snow Leopard|10.6.8]]; '''discontinued''')}}
* [[PowerPC]] {{small|([[Mac OS X 10.0|10.0]]–[[Mac OS X Leopard|10.5.8]]; '''discontinued''')}}
}}
| source_model        = [[Closed source software|Closed source]] (with [[open source software|open source]] components)
| working_state       = Current
| marketing_target    = Personal computing
| kernel_type         = [[Hybrid kernel|Hybrid]] ([[XNU]])<!-- It already says "Unix" under "family"; the kernel code came from Mach and BSD (and Apple's own work), not "Unix", and has its own name and Wikipedia page -->
| programmed_in       = {{flat list|
* [[C Programming Language|C]]
* [[C++]]
* {{nowrap|[[Objective-C]]}}
* [[Swift (programming language)|Swift]]<ref>{{Cite web|url=https://developer.apple.com/videos/play/wwdc2016/402/|title=What's New in Swift|date=June 14, 2016|website=[[Apple Developer]]|at=At 2:40|type=Video|access-date=June 16, 2016}}</ref>
}}
| updatemodel         = {{plain list|
* [[Mac App Store]] {{small|([[OS X Mountain Lion|10.8]]+)}}
* Software Update {{small|([[Mac OS X 10.0|10.0]]–[[Mac OS X Lion|10.7]])}}
}}
| preceded_by         = [[Classic Mac OS]]
| support_status = Supported
}}

'''macOS''' ({{IPAc-en|ˌ|m|æ|k|oʊ|ˈ|ɛ|s}};<ref>{{cite av media|url=https://www.apple.com/apple-events/june-2016/|time=36:28|title=Apple Events - WWDC Keynote June 2016}}</ref> previously '''Mac OS X''' and later '''OS X''') is the current series of [[Unix|Unix-based]] [[graphical user interface|graphical]] [[operating system]]s developed and marketed by [[Apple Inc.]] designed to run on Apple's [[Macintosh]] computers ("Macs"). It has been preinstalled on all Macs since 2002. Within the market of desktop, laptop and home computers, and by web usage, it is the [[Usage share of operating systems#Desktop and laptop computers|second most widely used desktop OS]] after [[Microsoft Windows]].<ref name="Net Applications">{{cite journal |url=http://www.netmarketshare.com/ |title=Desktop Operating System Market Share |publisher=Net Applications}}</ref><ref>{{cite web|url=http://gs.statcounter.com/#all-os-ww-monthly-201109-201508 |title=Top 8 Operating Systems from Sept 2011 to Aug 2015}}</ref>

Launched in 2001 as Mac OS X, the series is the latest in the family of [[Macintosh operating systems]]. Mac OS X succeeded [[Classic Mac OS|"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. Releases were [[code name]]d after [[big cat]]s from the original release up until [[OS X Mountain Lion|OS X 10.8 Mountain Lion]]. Beginning in 2013 with [[OS X Mavericks|OS X 10.9 Mavericks]], releases have been named after [[landmark]]s in [[California]].<ref name="techMavericks">{{cite web | url=https://techcrunch.com/2013/06/10/os-x-mavericks/ | title=Apple Has A New, California-Based Naming Scheme For OS X, Starting With OS X Mavericks | publisher=TechCrunch | date=June 10, 2013 | accessdate=June 10, 2013 | author=Ha, Anthony}}</ref> Apple changed the original name "Mac OS X" to "OS X" in 2012 and then to "macOS" in 2016, adopting the [[nomenclature]] that it uses for their other operating systems, [[iOS]], [[watchOS]], and [[tvOS]]. The latest version of macOS is [[macOS High Sierra]], which was publicly released in September 2017.

macOS is based on technologies developed at [[NeXT]] between 1985 and 1997, when Apple acquired the company. The "X" in Mac OS X and OS X is the [[Roman numerals#Symbols|Roman numeral]] for the number 10 and is pronounced as such. The X was a prominent part of the operating system's [[Brand#Brand identity|brand identity]], and was used to showcase its [[Unix]] compatibility; [[UNIX 03]] certification was achieved for the [[Intel]] version of [[Mac OS X Leopard|Mac OS X 10.5 Leopard]]<ref name=leopard_unix_cert>{{cite web | url=http://www.opengroup.org/openbrand/register/brand3555.htm | title=Mac OS X Version 10.5 on Intel-based Macintosh computers | publisher=The Open Group | accessdate=December 4, 2014
}}</ref> and all releases from [[Mac OS X Snow Leopard|Mac OS X 10.6 Snow Leopard]] up to the current version also have UNIX 03 certification.<ref name=sierra_unix_cert>{{cite web | url = http://www.opengroup.org/openbrand/register/brand3627.htm | title=macOS version 10.12 Sierra on Intel-based Mac computers | publisher=The Open Group| accessdate=September 29, 2016}}</ref><ref name=snow_leopard_unix_cert>{{cite web | url=http://www.opengroup.org/openbrand/register/brand3581.htm | title=Mac OS X Version 10.6 on Intel-based Macintosh computers | publisher=The Open Group | accessdate=December 4, 2014}}</ref><ref name=lion_unix_cert_claim>{{cite web | url=http://movies.apple.com/media/us/osx/2012/docs//OSX_for_UNIX_Users_TB_July2011.pdf | title=Apple technology brief on UNIX | publisher=[[Apple Inc.|Apple]] | accessdate=November 5, 2008}}</ref><ref name=mountain_lion_unix_cert>{{cite web | url=http://www.opengroup.org/openbrand/register/brand3591.htm | title=Mac OS X Version 10.8 on Intel-based Macintosh computers | publisher=The Open Group| accessdate=December 4, 2014}}</ref><ref name=mavericks_unix_cert>{{cite web | url = http://www.opengroup.org/openbrand/register/brand3602.htm | title=OS X Version 10.9 on Intel-based Macintosh computers | publisher=The Open Group | accessdate=December 4, 2014}}</ref><ref name=yosemite_unix_cert>{{cite web | url = http://www.opengroup.org/openbrand/register/brand3607.htm | title=OS X version 10.10 Yosemite on Intel-based Mac computers | publisher=The Open Group | accessdate=December 4, 2014}}</ref><ref name=el_capitan_unix_cert>{{cite web | url = http://www.opengroup.org/openbrand/register/brand3612.htm | title=OS X version 10.11 El Capitan on Intel-based Mac computers | publisher=The Open Group| accessdate=October 23, 2015}}</ref> macOS shares its Unix-based core, named [[Darwin (operating system)|Darwin]], and many of its [[software framework|frameworks]] with [[iOS]],<ref>{{cite web| first=Chris| last=Foresman| url=https://arstechnica.com/apple/news/2010/09/apple-tv-definitely-running-ios-could-be-jailbreak-target.ars| title=Apple TV definitely running iOS, could be jailbreak target| publisher=[[Condé Nast Publishing|Condé Nast Digital]] |work=[[Ars Technica]]|accessdate=November 16, 2010|date=September 2010}}</ref> [[tvOS]] and [[watchOS]]. A heavily modified version of [[Mac OS X Tiger|Mac OS X 10.4 Tiger]] was used for the first-generation [[Apple TV]].<ref>{{cite web| first=Walter S.| last=Mossberg| authorlink=Walt Mossberg| url=http://solution.allthingsd.com/20070321/pc-tv-via-apple/| title=From PC to TV&nbsp;– via Apple| work=[[All Things Digital]]|publisher=[[Dow Jones & Company]]|accessdate=May 18, 2008|date=March 21, 2007}}</ref>

Apple also used to have a [[macOS Server|separate line of releases]] of Mac OS X designed for [[server computing|servers]]. Beginning with [[Mac OS X Lion|Mac OS X 10.7 Lion]], the server functions were made available as a separate package on the [[Mac App Store]].

Releases of Mac OS X from 1999 to 2005 can run only on the [[PowerPC]]-based Macs from the time period. After Apple [[Apple's transition to Intel processors|announced that they were switching to Intel CPUs]] from 2006 onwards, a separate version of [[Mac OS X Tiger|Mac OS X 10.4 Tiger]] was made and distributed exclusively with early Intel-based Macs; it included an emulator known as [[Rosetta (software)|Rosetta]], which allowed users to run most PowerPC applications on Intel-based Macs. [[Mac OS X Leopard|Mac OS X 10.5 Leopard]] was released as a [[Universal binary]], meaning the installer disc supported both Intel and PowerPC processors. In 2009, Apple released [[Mac OS X Snow Leopard|Mac OS X 10.6 Snow Leopard]], which ran exclusively on Intel-based Macs. In 2011, Apple released [[Mac OS X Lion|Mac OS X 10.7 Lion]], which no longer supported 32-bit Intel processors and also did not include Rosetta. All versions of the system released since then run exclusively on [[64-bit computing|64-bit]] Intel CPUs and do not support PowerPC applications.{{OS X topics}}

==History==

===Development===
[[File:Unix timeline.en.svg|thumb|450px|Simplified history of [[Unix-like]] operating systems]]
{{Main|History of macOS}}

The heritage of what would become macOS had originated at [[NeXT]], a company founded by [[Steve Jobs]] following his departure from Apple in 1985. There, the [[Unix-like]] [[NeXTSTEP]] operating system was developed, and then launched in 1989. The [[kernel (operating system)|kernel]] of NeXTSTEP is based upon the [[Mach kernel]], which was originally developed at [[Carnegie Mellon University]], with additional kernel layers and low-level [[user space]] code derived from parts of [[BSD]]. Its [[graphical user interface]] was built on top of an [[object-oriented]] [[GUI toolkit]] using the {{nowrap|[[Objective-C]]}} programming language.

Throughout the early 1990s, Apple had tried to create a "next-generation" OS to succeed its [[classic Mac OS]] through the [[Taligent]], [[Copland (operating system)|Copland]] and [[Gershwin operating system|Gershwin]] projects, but all of them were eventually abandoned.<ref>{{cite web | url=http://www.theapplemuseum.com/index.php?id=44 | title=Apple Facts | accessdate=December 15, 2008 | publisher=The Apple Museum | quote=a joint venture with IBM, called Taligent, but was discontinued soon thereafter}}</ref> This led Apple to purchase [[NeXT]] in 1996, allowing NeXTSTEP, then called [[OpenStep|OPENSTEP]], to serve as the basis for Apple's next generation operating system.<ref>{{cite news | url=https://query.nytimes.com/gst/fullpage.html?res=9F06E1D71331F930A15751C1A960958260 | title=Why Apple Sees Next as a Match Made in Heaven | last=Markoff | first=John | work=[[The New York Times]] | publisher=[[The New York Times Company]] | date=December 23, 1996 | page=D1}}</ref>
This purchase also led to Steve Jobs returning to Apple as an interim, and then the permanent CEO, shepherding the transformation of the programmer-friendly OPENSTEP into a system that would be adopted by Apple's primary market of home users and creative professionals. The project was first code named "[[Rhapsody (operating system)|Rhapsody]]" and then officially named Mac OS X.<ref>{{cite web | first= Neil | last= Fawcett | title=Rhapsody suffers an identity crisis | url=http://business.highbeam.com/411267/article-1G1-20334085/rhapsody-suffers-identity-crisis | accessdate=April 19, 2012 | date=February 12, 1998 | work = [[Computer Weekly]] | publisher = [[Reed Business Information]]}} {{subscription required}}</ref><ref name="Rhapsody and Blues">{{cite web|last1=Siracusa|first1=John|title=Rhapsody and Blues|url=https://arstechnica.com/apple/2011/05/mac-os-x-revisited/|website=[[Ars Technica]]|accessdate=30 November 2015}}</ref>

===Mac OS X===

====Launch of Mac OS X====
Mac OS X was originally presented as the tenth major version of Apple's operating system for [[Macintosh]] computers; current versions of macOS retain the major version number "10". Previous Macintosh operating systems (versions of the [[classic Mac OS]]) were named using [[Arabic numerals]], as with [[Mac OS 8]] and [[Mac OS 9]]. The letter "X" in Mac OS X's name refers to the number 10, a [[Roman numeral]]. It is therefore correctly pronounced "ten" {{IPAc-en|ˈ|t|ɛ|n}} in this context.<ref name="ten_not_x">{{cite web|url=http://support.apple.com/kb/TA22541|title=What is an operating system (OS)?|publisher=[[Apple Inc.|Apple]]|quote=The current version of Mac OS is Mac OS X (pronounced "Mac O-S ten").|date=July 15, 2004|accessdate=December 20, 2006}}</ref><ref>{{cite web|url=https://arstechnica.com/apple/reviews/2006/03/osx-fiveyears.ars|title=Five years of Mac OS X|publisher=[[Condé Nast Publishing|Condé Nast Digital]]|work=[[Ars Technica]]|first=John|last=Siracusa|quote=Even Steve Jobs still says "ecks" instead of "ten" sometimes.|date=March 24, 2006|accessdate=April 15, 2009}}</ref> However, it is also commonly pronounced like the letter "X" {{IPAc-en|ˈ|ɛ|k|s}}.<ref name="BBC OSX name">{{cite av media|url=http://www.bbc.co.uk/iplayer/episode/b00z8dnj/Click_26_02_2011|title=Click - BBC TV programme|publisher=[[BBC]]|last=Kelly|first=Spencer|at=00:12:45|quote=Of course X {{IPAc-en|ˈ|ɛ|k|s}} does mean 10, but anyone who used to poke around on Unix systems will know that in those days anything Unix had an X (ˈɛks) in it, and OS Ten is written OS X (ˈɛks) in honour of the fact that it is based on Unix, unlike its predecessors. So, hey, you can say it any way you want; me, I'm showing my age and sticking with X (ˈɛks).|date=February 26, 2011|accessdate=March 20, 2011}}</ref>

The first version of Mac OS X, [[Mac OS X Server 1.0]], was a transitional product, featuring an interface resembling the [[classic Mac OS]], though it was not compatible with software designed for the older system. Consumer releases of Mac OS X included more [[backward compatibility]]. Mac OS applications could be rewritten to run natively via the [[Carbon API]]; many could also be run directly through the [[Classic Environment]] with a reduction in performance.

The consumer version of Mac OS X was launched in 2001 with [[Mac OS X 10.0]]. Reviews were variable, with extensive praise for its sophisticated, glossy [[Aqua (user interface)|Aqua interface]] but criticizing it for sluggish performance.<ref name="Siracusa decade of Mac OS X reviews">{{cite web|last1=Siracusa|first1=John|title=Here’s to the crazy ones: a decade of Mac OS X reviews|url=https://arstechnica.com/apple/2011/05/mac-os-x-revisited/2|website=[[Ars Technica]]|date=May 13, 2011|accessdate=November 30, 2015}}</ref> With Apple's popularity at a low, the makers of several classic Mac applications such as [[FrameMaker]] and [[PageMaker]] declined to develop new versions of their software for Mac OS X.<ref name="Adobe discontinues FrameMaker for Macintosh">{{cite web|last1=Dalrymple|first1=Jim|title=Adobe discontinues FrameMaker for Macintosh|url=http://www.macworld.com/article/1030037/framemaker.html|website=[[Macworld]]|date=March 23, 2004|accessdate=30 November 2015}}</ref> ''[[Ars Technica]]'' columnist John Siracusa, who reviewed every major OS X release up to 10.10, described the early releases in retrospect as 'dog-slow, feature poor' and Aqua as 'unbearably slow and a huge resource hog'.<ref name="Siracusa decade of Mac OS X reviews" /><ref name="Lion review Siracusa" /><ref name="Jon Rubinstein sends message to HP staff; Addresses TouchPad reviews">{{cite web|last1=Rubenstein|first1=John|title=Jon Rubinstein sends message to HP staff; Addresses TouchPad reviews|url=http://www.webosnation.com/jon-rubenstein-sends-message-hp-staff-addresses-touchpad-reviews|website=WebOS Nation|date=July 1, 2011|accessdate=November 30, 2015}}</ref>

====Following releases====
Apple rapidly developed several new releases of Mac OS X.<ref>{{cite web | first=Joel | last=Spolsky | title=How Microsoft Lost the API War | url=http://www.joelonsoftware.com/articles/APIWar.html | date=June 13, 2004 | accessdate=April 15, 2009 | quote=The developers of the Macintosh OS at Apple have always been in this camp [i.e. not trying to be backwards compatible no matter what]. It's why so few applications from the early days of the Macintosh still work...}}</ref> Siracusa's review of version 10.3, [[Mac OS X Panther|Panther]], noted "It's strange to have gone from years of uncertainty and [[vaporware]] to a steady annual supply of major new operating system releases."<ref name="OS X Panther review Siracusa">{{cite web|last1=Siracusa|first1=John|title=OS X Panther review|url=https://arstechnica.com/apple/2003/11/macosx-10-3/|website=[[Ars Technica]]|accessdate=30 November 2015}}</ref> Version 10.4, [[OS X Tiger|Tiger]], reportedly shocked executives at [[Microsoft]] by offering a number of features, such as fast file searching and improved graphics processing, that Microsoft had spent [[Development of Windows Vista|several years struggling]] to add to [[Windows]] with acceptable performance.<ref>{{cite web|url=http://www.informationweek.co.uk/microsofts-vista-had-major-mac-envy-comp/197001418|title=Microsoft's Vista Had Major Mac Envy, Company E-Mails Reveal|author=Gregg Keizer| publisher=Information Week|date=January 29, 2007|accessdate=February 28, 2013}}</ref>

As the operating system evolved, it moved away from the [[classic Mac OS]], with applications being added and removed.<ref name="Orlowski Jaguar review">{{cite web|last1=Orlowski|first1=Andrew|authorlink1=Andrew Orlowski|title=The Jagwyre Review|url=https://www.theregister.co.uk/2002/08/27/the_jagwyre_review/|website=The Register|accessdate=19 September 2017|quote=Using Mac OS X is like touring a land of fabulous ancient treasures - with a tourist authority that's still busy renovating them, and that hasn't quite completed the infrastructure.  The sights can be breathtaking, but the roads are potholed and incomplete, and sometimes you have to get out and push.  There are a few magnificent modern additions - Rendezvous, AppleScript Studio, for example - but in places the modern Apple archaeologists seem to have forgotten their ancestors techniques, and have resorted to inferior contemporary methods such as the Windows bodge of using three letter extensions for identifying the file type.}}</ref> Considering music to be a key market, Apple developed the [[iPod]] music player and music software for the Mac, including [[iTunes]] and [[GarageBand]].<ref name="Apple and the Oak Tree">{{cite web|last1=Thompson|first1=Ben|title=Apple and the Oak Tree|url=https://stratechery.com/2017/apple-and-the-oak-tree/|website=Stratechery|accessdate=19 September 2017}}</ref> Targeting the consumer and media markets, Apple emphasized its new "digital lifestyle" applications such as the [[iLife]] suite, integrated home entertainment through the [[Front Row (software)|Front Row]] media center and the [[Safari (browser)|Safari]] web browser. With increasing popularity of the internet, Apple offered additional online services, including the .Mac, [[MobileMe]] and most recently [[iCloud]] products. It later began selling third-party applications through the [[Mac App Store]]. 

Newer versions of Mac OS X also included modifications to the general interface, moving away from the striped gloss and transparency of the initial versions. Some applications began to use a [[Brushed Metal (interface)|brushed metal]] appearance, or non-pinstriped titlebar appearance in version 10.4.<ref>{{cite web | first=John | last=Rizzo | url=http://www.builderau.com.au/news/soa/Mac-OS-X-10-3-Panther/0,339028227,320280883,00.htm | title=Mac OS X 10.3 Panther | accessdate=April 15, 2009 | date=November 12, 2003 | quote=Once you reboot, you'll notice that Apple has abandoned the light and airy Aqua interface for the darker, heavier brushed-metal look of iTunes.}}</ref> In Leopard, Apple announced a unification of the interface, with a standardized gray-gradient window style.<ref>{{cite web | url=http://helpdesk.wisc.edu/page.php?id=6609 | publisher=University of Wisconsin | accessdate=April 15, 2009 | date=May 27, 2008 | first=Jeff | last=W. | title=Mac OS X (10.5)&nbsp;– User Interface Changes}}</ref><ref name="OS X Leopard review Siracusa">{{cite web|last1=Siracusa|first1=John|title=OS X Leopard review|url=https://arstechnica.com/apple/2007/10/mac-os-x-10-5/|website=[[Ars Technica]]|accessdate=30 November 2015}}</ref>

In 2006, the first [[Intel]] Macs released used a specialized version of [[Mac OS X Tiger|Mac OS X 10.4 Tiger]].<ref>{{cite web|title = Mac OS X versions (builds) for computers – Apple Support|url = https://support.apple.com/en-us/HT204319|website = support.apple.com|accessdate = May 24, 2015}}</ref> In 2007, [[Mac OS X Leopard|Mac OS X 10.5 Leopard]] was the first to run on both PowerPC and Intel Macs with the use of [[Universal binary|universal binaries]].<ref>{{cite web|title = Apple – Press Info – Apple to Ship Mac OS X Leopard on October 26|url = https://www.apple.com/pr/library/2007/10/16Apple-to-Ship-Mac-OS-X-Leopard-on-October-26.html|website = www.apple.com|accessdate = May 24, 2015}}</ref> [[Mac OS X Snow Leopard|Mac OS X 10.6 Snow Leopard]] was the first version of OS X to drop support for [[PowerPC]] Macs.<ref>{{cite web|title = Mac OS X 10.6 Snow Leopard|url = http://store.apple.com/us/product/MC573Z/A/mac-os-x-106-snow-leopard|website = Apple Store (U.S.)|accessdate = May 24, 2015}}</ref>

A key development for the system was the announcement and release of the [[iPhone]] from 2007 onwards. While Apple's previous [[iPod classic|iPod]] media players used a [[Embedded operating system|minimal]] operating system, the iPhone used an operating system based on Mac OS X, which would later be called "iPhone OS" and then [[iOS]]. The simultaneous release of two operating systems based on the same frameworks placed tension on Apple, which cited the iPhone as forcing it to delay [[Mac OS X Leopard|Mac OS X 10.5 Leopard]].<ref name="Apple announces Leopard delays due to the iPhone">{{cite web|last1=Chartier|first1=David|title=Apple announces Leopard delays due to the iPhone|url=https://www.engadget.com/2007/04/12/apple-announces-leopard-delays-due-to-the-iphone/|website=Engadget|accessdate=30 November 2015}}</ref> However, after Apple opened the iPhone to third-party developers its commercial success drew attention to Mac OS X, with many iPhone software developers showing interest in Mac development.<ref name="WWDC 2009 Wrap-Up">{{cite web|last1=Gruber|first1=John|title=WWDC 2009 Wrap-Up|url=http://daringfireball.net/2009/06/wwdc09_wrapup|website=Daring Fireball|accessdate=30 November 2015}}</ref>

In two succeeding versions, [[OS X Lion|Lion]] and [[OS X Mountain Lion|Mountain Lion]], Apple moved some applications to a highly [[Skeuomorph#Use in Apple products|skeuomorphic]] style of design inspired by contemporary versions of iOS, at the same time simplifying some elements by making controls such as scroll bars fade out when not in use.<ref name="Lion review Siracusa">{{cite web|last1=Siracusa|first1=John|title=Lion review|url=https://arstechnica.com/apple/2011/07/mac-os-x-10-7/|website=[[Ars Technica]]}}</ref> This direction was, like brushed metal interfaces, unpopular with some users, although it continued a trend of greater animation and variety in the interface previously seen in design aspects such as the [[Time Machine (OS X)|Time Machine]] [[Backup software|backup]] utility, which presented past file versions against a swirling nebula, and the glossy translucent [[Dock (OS X)|dock]] of [[OS X Leopard|Leopard]] and [[OS X Snow Leopard|Snow Leopard]].<ref name="Apple's History of Skeuomorphism">{{cite web|last1=Brand|first1=Thomas|title=Apple's History of Skeuomorphism|url=http://eggfreckles.net/notes/skeuomorphism.html|website=Egg Freckles|accessdate=30 November 2015}}</ref> In addition, with [[Mac OS X Lion|Mac OS X 10.7 Lion]], Apple ceased to release separate [[OS X Server|server]] versions of Mac OS X, selling server tools as a separate downloadable application through the Mac App Store. A review described the trend in the server products as becoming "cheaper and simpler... shifting its focus from large businesses to small ones."<ref name="Guide to OS X Server">{{cite web|last1=Cunningham|first1=Andrew|title=Server, simplified: A power user’s guide to OS X Server|url=https://arstechnica.com/apple/2012/07/the-server-simplified-a-power-users-guide-to-os-x-server/|website=[[Ars Technica]]|accessdate=2 December 2015}}</ref>

===OS X===
[[File:The OS X Logo.svg|thumb|200px|OS X logo from 2012–2013]]
In 2012, with the release of [[OS X Mountain Lion|OS X 10.8 Mountain Lion]], the name of the system was shortened from Mac OS X to OS X. That year, Apple removed the head of OS X development, [[Scott Forstall]], and design was changed towards a more minimal direction.<ref name="guardian">{{cite news|author=Charles Arthur, technology editor |url=https://www.theguardian.com/technology/2012/oct/30/apple-tim-cook-ruthless-streak |title=Apple's Tim Cook shows ruthless streak in firing maps and retail executives &#124; Technology &#124; guardian.co.uk |publisher=Guardian |date=2012-10-30 |accessdate=2012-12-06 |location=London}}</ref> Apple's new user interface design, using deep color saturation, text-only buttons and a minimal, 'flat' interface, was debuted with [[iOS 7]] in 2013. With OS X engineers reportedly working on iOS 7, the version released in 2013, [[OS X Mavericks|OS X 10.9 Mavericks]], was something of a transitional release, with some of the skeuomorphic design removed, while most of the general interface of Mavericks remained unchanged.<ref name="Siracusa OS X Mavericks review">{{cite web|last1=Siracusa|first1=John|title=OS X Mavericks review|url=https://arstechnica.com/apple/2013/10/os-x-10-9/|website=[[Ars Technica]]|accessdate=30 November 2015}}</ref> The next version, [[OS X Yosemite|OS X 10.10 Yosemite]], adopted a design similar to [[iOS 7]] but with greater complexity suitable for an interface controlled with a mouse.<ref name="OS X Yosemite review">{{cite web|last1=Siracusa|first1=John|title=OS X Yosemite review|url=https://arstechnica.com/apple/2014/10/os-x-10-10/|website=[[Ars Technica]]|accessdate=30 November 2015}}</ref>

From 2012 onwards, the system has shifted to an annual release schedule similar to that of [[iOS]]. It also steadily cut the cost of updates from Snow Leopard onwards, before removing upgrade fees altogether from 2013 onwards.<ref name="Mountain Lion Gruber Schiller">{{cite web|last1=Gruber|first1=John|title=Mountain Lion|url=https://daringfireball.net/2012/02/mountain_lion|website=Daring Fireball|accessdate=15 August 2015}}</ref> Some journalists and third-party software developers have suggested that this decision, while allowing more rapid feature release, meant less opportunity to focus on stability, with no version of OS X recommendable for users requiring stability and performance above new features.<ref name="Apple has lost the functional high ground">{{cite web|last1=Arment|first1=Marco|title=Apple has lost the functional high ground|url=http://www.marco.org/2015/01/04/apple-lost-functional-high-ground|accessdate=15 August 2015}}</ref> Apple's 2015 update, [[OS X El Capitan|OS X 10.11 El Capitan]], was announced to focus specifically on stability and performance improvements.<ref>{{Cite news|url=http://www.macworld.co.uk/review/mac-software/mac-os-x-el-capitan-mac-review-3613524/|title=Mac OS X El Capitan review: The best (and worst) new features|last=Hattersley|first=Lucy|work=Macworld UK|access-date=2017-05-19|language=en-GB}}</ref>

===macOS===
In 2016, with the release of [[macOS Sierra|macOS 10.12 Sierra]], the name was changed from OS X to macOS to streamline it with the branding of Apple's other primary operating systems: [[iOS]], [[watchOS]], and [[tvOS]].<ref>{{Cite news|url=http://www.businessinsider.com/wwdc-2016-os-x-becomes-macos-2016-6|title=Apple just renamed one of its oldest and most important products|last=|first=|date=June 13, 2016|work=|newspaper=Business Insider|access-date=November 11, 2016|via=}}</ref>

macOS 10.12 Sierra's main features are the introduction of [[Siri]] to macOS, Optimized Storage, improvements to included applications, and greater integration with Apple's [[iPhone]] and [[Apple Watch]]. The [[Apple File System]] (APFS) was announced at the [[Apple Worldwide Developers Conference]] in 2016 as a replacement for [[HFS+]], a highly criticized file system.<ref>{{cite av media|url=https://developer.apple.com/videos/play/wwdc2016/701/|title= Introducing Apple File System|publisher=Apple|year=2016}}</ref>

At the 2017 Worldwide Developers Conference Apple previewed [[macOS High Sierra|macOS 10.13 High Sierra]].  It uses APFS, rather than HFS+, on [[solid state drives]].

==Architecture==
{{Main|Architecture of macOS}}

At macOS's core is a [[POSIX]] compliant operating system built on top of the [[XNU]] [[kernel (computer science)|kernel]], with standard Unix facilities available from the [[command line interface]]. Apple has released this family of software as a [[free software|free]] and [[open source software|open source]] operating system named [[Darwin (operating system)|Darwin]]. On top of Darwin, Apple layered a number of components, including the [[Aqua (user interface)|Aqua]] interface and the [[Finder (software)|Finder]], to complete the [[Graphical User Interface|GUI]]-based operating system which is macOS.<ref name="aqua23">{{cite web | url=http://www.tuaw.com/2011/04/12/mac-os-x-lion-to-tone-down-the-aqua/ | title=Mac OS X Lion to tone down the Aqua | publisher=[[AOL]] | work=The Unofficial Apple Weblog | date=April 12, 2011 | accessdate=April 9, 2012 | author=Grothaus, Michael}}</ref>

With its original introduction as Mac OS X, the system brought a number of new capabilities to provide a more stable and reliable platform than its predecessor, the [[classic Mac OS]]. For example, [[pre-emptive multitasking]] and [[memory protection]] improved the system's ability to run multiple applications simultaneously without them interrupting or corrupting each other.<ref>{{cite web | first=Eric Steven | last=Raymond | title=The Elements of Operating-System Style | url=http://www.faqs.org/docs/artu/ch03s01.html#id2892085 | accessdate=November 5, 2008}}</ref>
Many aspects of macOS's architecture are derived from [[OpenStep|OPENSTEP]], which was designed to be portable, to ease the transition from one platform to another. For example, [[NeXTSTEP]] was ported from the original [[68k]]-based NeXT workstations to [[x86]] and other architectures before NeXT was purchased by Apple,<ref name="nextstep_history" />
and OPENSTEP was later ported to the [[PowerPC]] architecture as part of the [[Rhapsody (operating system)|Rhapsody project]].

Prior to macOS High Sierra, and on drives other than [[solid state drives]] (SSDs), the default [[file system]] is [[HFS Plus|HFS+]], which it inherited from the classic Mac OS. Operating system designer [[Linus Torvalds]] has criticized HFS+, saying it is "probably the worst file system ever", whose design is "actively corrupting user data". He criticized the [[case insensitivity]] of file names, a design made worse when Apple extended the file system to support [[Unicode]].<ref>{{cite web|url=http://www.itworld.com/article/2868393/linus-torvalds-apples-hfs-is-probably-the-worst-file-system-ever.html|title=Linus Torvalds: Apple's HFS+ is probably the worst file system ever|author=Swapnil Bhartiya|date=January 13, 2015|work=CIO}}</ref><ref>{{cite web|url=https://plus.google.com/+JunioCHamano/posts/1Bpaj3e3Rru|title=CVE-2014-9390 aka "Git on case-insensitive filesystems"I did not give the…|work=google.com}}</ref> Initially, HFS+ was designed for classic Mac OS, which runs on [[big-endian]] [[68K]] and [[PowerPC]] systems. When Apple switched Macintosh to little-endian Intel processors, it continued to use big-endian byte order on HFS+ file systems. As a result, macOS on current Macs must do [[byte swap]] when it reads file system data.<ref>{{cite web|url=http://www.zdnet.com/article/wwdcs-biggest-disappointment/|title=WWDC's biggest disappointment|author=Robin Harris|work=ZDNet}}</ref><ref>{{cite web|url=https://arstechnica.com/apple/2011/07/mac-os-x-10-7/12/|title=Mac OS X 10.7 Lion: the Ars Technica review|work=Ars Technica}}</ref> These concerns are being addressed with the new [[Apple File System]], which is used for file systems on SSDs in macOS High Sierra.

The [[Darwin (operating system)|Darwin]] subsystem in macOS is in charge of managing the file system, which includes the Unix [[File system permissions|permissions]] layer. In 2003 and 2005, two [[Macworld]] editors expressed criticism of the permission scheme; Ted Landau called misconfigured permissions "the most common frustration" in macOS, while Rob Griffiths suggested that some users may even have to [[Repair permissions|reset permissions]] every day, a process which can take up to 15 minutes.<ref>{{cite web | first=Rob | last=Griffiths | title=Prevent Mac Disasters | url=http://www.macworld.com/article/42286/2005/01/preventmacdisasters.html | work=[[Macworld]] |publisher=[[International Data Group|IDG]] |date=February 2005 | accessdate=February 8, 2009}}</ref> More recently, another Macworld editor, Dan Frakes, called the procedure of repairing permissions vastly overused.<ref>{{cite web | first=Dan | last=Frakes | title=Repairing permissions: what you need to know | url=http://www.macworld.com/article/52220/2006/08/repairpermissions.html | work=[[Macworld]] | publisher=[[International Data Group|IDG]] |date=August 2006 | accessdate=February 8, 2009}}</ref> He argues that macOS typically handles permissions properly without user interference, and resetting permissions should just be tried when problems emerge.<ref>{{cite web | first=Dan | last=Frakes | title=Five Mac maintenance myths | url=http://www.macworld.com/article/133684/2008/06/maintenance_intro.html | work=[[Macworld]] |publisher=[[International Data Group|IDG]] |date=June 2008 | accessdate=February 8, 2009}}</ref>

The architecture of macOS incorporates a layered design:<ref>{{cite web|url=https://developer.apple.com/library/mac/#documentation/MacOSX/Conceptual/OSX_Technology_Overview/About/About.html |title=About the Technologies for Developing Mac OS X Software |publisher=[[Apple Inc.|Apple]] |accessdate=April 4, 2012}}</ref>
the layered frameworks aid rapid development of applications by providing existing code for common tasks.<ref>{{cite web  | first=Tom | last=Zepko | url=http://homepage.mac.com/tom_zepko/cocoa/why-cocoa.html | title=Why Cocoa? | accessdate=April 15, 2009 | date=November 6, 2003}}</ref> Apple provides its own [[software development]] tools, most prominently an [[integrated development environment]] called [[Xcode]]. Xcode provides interfaces to [[compiler]]s that support several [[programming language]]s including [[C (programming language)|C]], [[C++]], [[Objective-C]], and [[Swift (programming language)|Swift]]. For the [[Apple–Intel transition]], it was modified so that developers could build their applications as a [[universal binary]], which provides compatibility with both the Intel-based and PowerPC-based Macintosh lines.<ref>{{cite web | url=https://developer.apple.com/macosx/adoptinguniversalbinaries.html | title=Adopting Universal Binaries on Mac OS X | accessdate=December 15, 2008 | date=February 22, 2007 | publisher=[[Apple Inc.|Apple]]}}</ref> First and third-party applications can be controlled programatically using the [[AppleScript]] framework,<ref>{{Cite web|url=http://www.macosxautomation.com/applescript/uiscripting/|title=AppleScript: Graphic User Interface (GUI) Scripting|last=Productions|first=Nyhthawk|website=www.macosxautomation.com|access-date=2017-01-03}}</ref> retained from the [[classic Mac OS]],<ref>{{Cite web|url=http://whitefiles.org/b1_s/1_free_guides/fg3mo/pgs/v01.htm|title=AppleScript Introduction|website=whitefiles.org|access-date=2017-01-03}}</ref> or using the newer [[Automator (software)|Automator]] application that offers pre-written tasks that do not require programming knowledge.<ref>{{Cite web|url=http://www.rawinfopages.com/mac/content/really-simple-guide-automator-os-x-mac|title=The really simple guide to Automator in OS X on the Mac {{!}} RAW Mac|website=www.rawinfopages.com|access-date=2017-01-03}}</ref>

===Software compatibility===
{{See also|List of Macintosh software}}
{| class="wikitable" style="text-align:center"
|+ List of macOS versions and the software they run
|-
! Operating system
! [[Safari (web browser)|Safari]]
! [[Mail (Apple)|Mail]]
! [[QuickTime]]
! [[iTunes]]
! [[Messages (Apple)|Messages]]/[[iChat]]
! [[iWork]]
|-
! style="text-align: left;" | [[macOS High Sierra|10.13 "High Sierra"]]
| rowspan="3" | 11.0
| rowspan="2" | 11.0
| rowspan="4" | 10.4
| rowspan="4" | 12.7
| 11.0
| rowspan="2" | 2017
|-
! style="text-align: left;" | [[macOS Sierra|10.12 "Sierra"]]
| 10.0
|-
! style="text-align: left;" | [[OS X El Capitan|10.11 "El Capitan"]]
| rowspan="2" | 9.3
| 9.2
| 2016
|-
! style="text-align: left;" | [[OS X Yosemite|10.10 "Yosemite"]]
| rowspan="2" | 9.1.3
| rowspan="3" | 8.0
| 2014
|-
! style="text-align: left;" | [[OS X Mavericks|10.9 "Mavericks"]]
| 7.3
| 10.3
| 12.6.2
| 2013
|-
! style="text-align: left;" | [[OS X Mountain Lion|10.8 "Mountain Lion"]]
| rowspan="2" | 6.1
| rowspan="2" {{dunno}}
| 10.2
| 12.4.3<ref>{{cite web|title=iTunes - Download iTunes Now |url=https://www.apple.com/itunes/download/ |website=Apple |accessdate=September 16, 2017 |archiveurl=https://web.archive.org/web/20160905124649/http://www.apple.com/itunes/download/ |archivedate=September 5, 2016 |date=June 1, 2016}}</ref>
| rowspan="5" | '09
|-
! style="text-align: left;" | [[Mac OS X Lion|10.7 "Lion"]] <ref group="note" name="MessagesLion"/>
| rowspan="2" | 10.1
| 12.2.2<ref>{{cite web|title=iTunes - Download iTunes Now |url=https://www.apple.com/itunes/download/ |website=Apple |accessdate=April 16, 2017 |archiveurl=https://web.archive.org/web/20150916003346/http://www.apple.com/itunes/download/ |archivedate=September 16, 2015 |date=September 16, 2015}}</ref>
| 8.0b or 6.0.1
|-
! style="text-align: left;" | [[Mac OS X Snow Leopard|10.6 "Snow Leopard"]]
| 5.1.10<ref>{{cite web|title=Safari 5.1.10 for Snow Leopard|url=https://support.apple.com/kb/DL1569|website=Apple|accessdate=April 16, 2017|language=en|date=September 12, 2013}}</ref>
| 4.5<ref>{{cite web|title=Mac OS X v10.6: "You can‘t use this version of Mail…" alert after installing Security Update 2012-004|url=https://support.apple.com/HT203684|website=Apple|accessdate=April 16, 2017|date=March 23, 2016}}</ref>
| 11.4<ref>{{cite web|title=iTunes 11.4 for OS X 10.6|url=https://support.apple.com/kb/DL1774|website=Apple|accessdate=April 16, 2017|language=en|date=September 9, 2014}}</ref>
| 5.0

|-
! style="text-align: left;" | [[Mac OS X Leopard|10.5 "Leopard"]]
| 5.0.6
| 3.6
| 7.7
| 10.6.3<ref>{{cite web|title=iTunes 10.6.3|url=https://support.apple.com/kb/DL1575|website=Apple|accessdate=April 16, 2017|language=en|date=June 11, 2012}}</ref>
| 4.0

|-
! style="text-align: left;" | [[Mac OS X Tiger|10.4 "Tiger"]]
| 4.1.3
| 2.1.3
| 7.6.4
| 9.2.1<ref>{{cite web|title=iTunes 9.2.1|url=https://support.apple.com/kb/DL1056|website=Apple|accessdate=April 16, 2017|language=en|date=July 19, 2010}}</ref>
| 3.0

|-
! style="text-align: left;" | [[Mac OS X Panther|10.3 "Panther"]]
| 1.3.2
| rowspan="4" | 1.x
| 7.5
| 7.7.1<ref>{{cite web|title=iTunes 7.7.1 for Panther|url=https://discussions.apple.com/thread/4239503?start=0&tstart=0|website=Official Apple Support Communities|accessdate=April 16, 2017|date=August 25, 2012}}</ref>
| 2.1<ref>{{cite web|title=iChat AV 2.1 |url=https://www.apple.com/support/downloads/ichatav21.html |website=Apple |accessdate=March 16, 2017 |archiveurl=https://web.archive.org/web/20070429174825/http://www.apple.com/support/downloads/ichatav21.html |archivedate=April 29, 2007 |date=March 23, 2004 |deadurl=yes |df= }}</ref>
| '05
|-
! style="text-align: left;" | [[Mac OS X 10.2|10.2 "Jaguar"]] <ref group="note" name="KeynoteJaguar"/>
| 1.0.3
| 6.5.3
| 6.0.5
| 2.0
| [[Keynote (presentation software)|Keynote]]
|-
! style="text-align: left;" | [[Mac OS X 10.1|10.1 "Puma"]]
| rowspan="2" {{n/a}}
| 6.3.1
| 4.7.1
| rowspan="2" {{n/a}}
| rowspan="2" {{n/a}}
|-
! style="text-align: left;" | [[Mac OS X 10.0|10.0 "Cheetah"]] <ref group="note" name="iTunesClassic"/>
| 5.0
| 2.0.4
|}
{{Reflist|group="note"|refs=
<ref group="note" name="MessagesLion">[https://www.macrumors.com/2012/02/17/after-beta-messages-will-be-exclusive-to-os-x-mountain-lion/ Messages 8.0b] was a beta release that only functioned from February 16 to December 12, 2012. Afterwards, users could either revert to iChat or upgrade to a newer version of OS X (10.8 "Mountain Lion" for US$19.99, or 10.9 "Mavericks" or newer for free) to continue using Messages.</ref>
<ref group="note" name="KeynoteJaguar">[https://web.archive.org/web/20030109062111/http://store.apple.com/1-800-MY-APPLE/WebObjects/AppleStore?productLearnMore=M8820Z%2FA Keynote 1.0] is the only iLife program that is compatible with Mac OS X 10.2 "Jaguar". Two minor updates, 1.1 and 1.1.1, can be applied to this version.</ref>
<ref group="note" name="iTunesClassic">iTunes 2.0.4 can only run if [[List of macOS components#Classic|Classic]] is installed. Otherwise, Mac OS X 10.0 can only run iTunes 1.1.1 natively.</ref>}}

Apple offered two main [[Application programming interface|APIs]] to develop software natively for macOS: [[Cocoa (API)|Cocoa]] and [[Carbon (API)|Carbon]]. Cocoa was a descendant of APIs inherited from [[OpenStep|OPENSTEP]] with no ancestry from the [[classic Mac OS]], while Carbon was an adaptation of classic Mac OS APIs, allowing Mac software to be minimally rewritten in order to run natively on Mac OS X.

The Cocoa API was created as the result of a 1993 collaboration between [[NeXT|NeXT Computer]] and [[Sun Microsystems]]. This heritage is highly visible for Cocoa developers, since the "NS" prefix is ubiquitous in the framework, standing variously for '''N'''eXT'''S'''TEP or '''N'''eXT/[[Sun Microsystems|'''S'''un]]. The official OPENSTEP API, published in September 1994, was the first to split the API between Foundation and ApplicationKit and the first to use the "NS" prefix.<ref name="nextstep_history">{{cite web |url=https://developer.apple.com/library/mac/documentation/cocoa/conceptual/cocoafundamentals/WhatIsCocoa/WhatIsCocoa.html#//apple_ref/doc/uid/TP40002974-CH3-SW12 | title=Cocoa Fundamentals Guide: A Bit of History | accessdate=December 15, 2008 | publisher=[[Apple Developer Connection]] | work=ADC Reference Library}}</ref> Traditionally, Cocoa programs have been mostly written in [[Objective-C]], with Java as an alternative. However, on July 11, 2005, Apple announced that "features added to Cocoa in Mac OS X versions later than 10.4 will not be added to the Cocoa-Java programming interface."<ref>{{cite web |url=https://developer.apple.com/legacy/mac/library/#documentation/Cocoa/Conceptual/LanguageIntegration/LanguageIntegration.html | title=Introduction to Cocoa-Java Integration Guide | accessdate=April 8, 2006 | publisher=[[Apple Developer Connection]] | work=ADC Reference Library}}</ref> macOS also used to support the [[Java Platform]] as a "preferred software package"—in practice this means that applications written in Java fit as neatly into the operating system as possible while still being [[cross-platform]] compatible, and that graphical user interfaces written in [[Swing (Java)|Swing]] look almost exactly like native Cocoa interfaces. Since 2014, Apple has promoted its new programming language [[Swift (programming language)|Swift]] as the preferred language for software development on Apple platforms.

Apple's original plan with macOS was to require all developers to rewrite their software into the Cocoa APIs. This caused much outcry among existing Mac developers, who threatened to abandon the platform rather than invest in a costly rewrite, and the idea was shelved.<ref name="Rhapsody and Blues" /><ref name="Photoshop, Lightroom, and Adobe's 64-bit roadmap" /> To permit a smooth transition from Mac OS 9 to Mac OS X, the [[Carbon (API)|Carbon]] [[Application Programming Interface]] (API) was created.<ref name="Rhapsody and Blues" /> Applications written with Carbon were initially able to run natively on both classic Mac OS and Mac OS X, although this ability was later dropped as Mac OS X developed. Carbon was not included in the first product sold as Mac OS X: the little-used original release of [[Mac OS X Server 1.0]], which also did not include the Aqua interface.<ref>{{Cite news|url=http://www.macworld.com/article/1154036/software-utilities/osxorigins.html|title=Looking back at OS X's origins|work=Macworld|access-date=2017-04-17|language=en}}</ref> Apple limited further development of Carbon from the release of Leopard onwards, announcing Carbon applications would not receive the ability to run at [[64-bit computing|64-bit]].<ref name="Photoshop, Lightroom, and Adobe's 64-bit roadmap">{{cite web|last1=Nack |first1=John |title=Photoshop, Lightroom, and Adobe's 64-bit roadmap |url=http://blogs.adobe.com/jnack/2008/04/photoshop_lightroom_and_adobes_64-bit_road.html |publisher=[[Adobe Systems]] |accessdate=March 30, 2016}}</ref> As of 2015, a small number of older Mac OS X apps with heritage dating back to the classic Mac OS still used Carbon, including [[Microsoft Office]]. Early versions of macOS could also run some classic Mac OS applications through the [[Classic Environment]] with performance limitations; this feature was removed from 10.5 onwards and all Macs using Intel processors.

Because macOS is [[POSIX]] compliant, many software packages written for the other [[Unix-like]] systems such as [[Linux]] can be recompiled to run on it, including much scientific and technical software.<ref name=Mainzer>{{cite web|last1=Steele|first1=Billy|title=NASA WISE Deputy Project Scientist Amy Mainzer|url=https://www.engadget.com/2013/05/24/engadget-questionnaire-nasa-amy-mainzer/|website=Engadget|quote=As an astrophysicist, having the Unix core underlying the OS is key, since virtually all of our software is Unix-based in some sense}}</ref> Third-party projects such as [[Homebrew (package management software)|Homebrew]], [[Fink]], [[MacPorts]] and [[pkgsrc]] provide pre-compiled or pre-formatted packages. Apple and others have provided versions of the [[X Window System]] graphical interface which can allow these applications to run with an approximation of the macOS look-and-feel.<ref>{{cite web | title=X11 for Mac OS X 1.0 | date=October 28, 2003 | url=http://support.apple.com/downloads/X11_for_Mac_OS_X_1_0 | publisher=[[Apple Inc.|Apple]] | accessdate=December 15, 2008}}</ref><ref>{{cite web | url=http://lists.apple.com/archives/x11-users/2007/Oct/msg00065.html | title=Re: X11 in Leopard: xterm on start-up | author=Ben Byer | date=October 27, 2007 | work=Apple's x11-users mailing list | accessdate=January 18, 2008}}</ref><ref>{{cite web |url=https://www.phoronix.com/scan.php?page=news_item&px=OTQ5OA |title=X.Org Server 1.10.2 Brings A Bunch Of Bug-Fixes |author=Michael Larabel |date=May 28, 2011 |publisher=phoronix |accessdate=May 29, 2011}}</ref> The current Apple-endorsed method is the open-source [[XQuartz]] project; earlier versions could use the [[X11.app|X11]] application provided by Apple, or before that the [[XDarwin]] project.<ref>{{cite web | url=http://www.macrumors.com/2012/02/17/apple-removes-x11-in-os-x-mountain-lion-shifts-support-to-open-source-xquartz/ | title=Apple Removes X11 in OS X Mountain Lion, Shifts Support to Open Source XQuartz | publisher=MacRumors | date=February 17, 2012 | accessdate=February 23, 2012 |last=Slivka |first=Eric}}</ref>

Applications can be distributed to Macs and installed by the user from any source and by any method such as downloading (with or without [[code signing]], available via an Apple developer account) or through the [[Mac App Store]], a marketplace of software maintained by Apple by way of a process requiring the company's approval. Apps installed through the Mac App Store run within a [[Sandbox (computer security)|sandbox]], restricting their ability to exchange information with other applications or modify the core operating system and its features. This has been cited as an advantage, by allowing users to install apps with confidence that they should not be able to damage their system, but also as a disadvantage, by blocking the Mac App Store's use by professional applications that require elevated privileges.<ref name="Not on the Mac App Store">{{cite web|last1=Counsell|first1=Dan|title=Not on the Mac App Store|url=http://dancounsell.typed.com/articles/not-on-the-mac-app-store|accessdate=1 December 2015}}</ref><ref name="Distributing Apps Outside the Mac App Store">{{cite web|title=Distributing Apps Outside the Mac App Store|url=https://developer.apple.com/library/mac/documentation/IDEs/Conceptual/AppDistributionGuide/DistributingApplicationsOutside/DistributingApplicationsOutside.html|website=Apple Developer|publisher=Apple|accessdate=1 December 2015}}</ref> Applications without any code signature cannot be run by default except from a computer's administrator account.<ref name="How to open apps from an unidentified developer in OS X Mountain Lion">{{cite web|last1=Kazmucha|first1=Allyson|title=How to open apps from an unidentified developer in OS X Mountain Lion|url=http://www.imore.com/how-open-apps-unidentified-developer-os-x-mountain-lion|website=IMore|accessdate=1 December 2015}}</ref><ref name="About Gatekeeper">{{cite web|title=About Gatekeeper|url=https://support.apple.com/en-us/HT202491|publisher=Apple|accessdate=1 December 2015}}</ref>

Apple produces macOS applications, some of which are included and some sold separately. This includes [[iWork]], [[Final Cut Pro]], [[Logic Pro]], [[iLife]], and the database application [[FileMaker]]. Numerous other developers also offer [[List of Macintosh software|software for macOS]].

===Hardware compatibility===
{| class="wikitable" style="text-align:center"
|+ List of macOS versions, the supported systems on which they run, and their RAM requirements
|-
! Operating system
! Supported systems
! RAM requirement
|-
| [[macOS Sierra|10.12]] – [[macOS High Sierra|10.13]]
| Intel Macs <small>([[64-bit computing|64-bit]])</small> released in:<br/>2009 <small>(iMac and main [[MacBook]] line)</small>, 2010 <small>(other)</small> or later<ref>{{cite web|url=https://arstechnica.com/apple/2017/06/anything-that-can-run-macos-sierra-can-also-run-macos-xxx/|title=Anything that can run macOS Sierra can also run macOS High Sierra|author=Andrew Cunningham|date=June 5, 2017|website=[[Ars Technica]]}}</ref>
| rowspan="3" | 2 GB
|-
| [[OS X Mountain Lion|10.8]] – [[OS X El Capitan|10.11]]
| Intel Macs <small>(64-bit)</small> released in:<br/>2007 <small>(prosumer and iMac)</small>, 2008 <small>(other consumer)</small>, 2009 <small>(Xserve)</small> or later
|-
| [[Mac OS X Lion|10.7]]
| Intel Macs <small>(64-bit)</small><ref name="LionReq">{{Cite web|url=https://support.apple.com/en-au/HT202328|title=System requirements for OS X Lion and Mac OS X v10.6|language=en-AU|access-date=2016-09-22}}</ref><br/>[[Rosetta (software)|Rosetta]] support dropped from 10.7 and newer.
|-
| [[Mac OS X Snow Leopard|10.6]]
| Intel Macs <small>(32-bit or 64-bit)</small><ref name="LionReq"/>
| 1 GB
|-
| [[Mac OS X Leopard|10.5]]
| G4, G5 and Intel Macs <small>(32-bit or 64-bit)</small> at 867&nbsp;MHz or faster<br/>[[List of macOS components#Classic|Classic]] support dropped from 10.5 and newer.
| 512 MB
|-
| [[Mac OS X Tiger|10.4]]
| Macs with built-in [[FireWire]] and either a [[New World ROM]] or Intel processor
| 256 MB
|-
| [[Mac OS X Panther|10.3]]
| Macs with a [[New World ROM]]<ref name="TigerRequirements">{{cite web | accessdate=December 20, 2006 | date=April 28, 2005 | title=Mac OS X: System Requirements | url=http://docs.info.apple.com/article.html?artnum=106163 | publisher=[[Apple Inc.|Apple]]}}</ref>
| rowspan="2" | 128 MB
|-
| [[Mac OS X 10.0|10.0]] – [[Mac OS X 10.2|10.2]]
| G3, G4 and G5 [[iBook]] and [[PowerBook]], [[Power Macintosh|Power Mac]] and [[iMac]]<br/><small>(except [[PowerBook G3]] "Kanga")</small>
|}

Tools such as [[XPostFacto]] and patches applied to the installation media have been developed by third parties to enable installation of newer versions of macOS on systems not officially supported by Apple. This includes a number of pre-G3 Power Macintosh systems that can be made to run up to and including Mac OS X 10.2 Jaguar, all G3-based Macs which can run up to and including Tiger, and sub-867&nbsp;MHz G4 Macs can run Leopard by removing the restriction from the installation DVD or entering a command in the Mac's [[Open Firmware]] interface to tell the Leopard Installer that it has a clock rate of 867&nbsp;MHz or greater. Except for features requiring specific hardware such as graphics acceleration or DVD writing, the operating system offers the same functionality on all supported hardware.

As most Mac hardware components, or components similar to those, since the Intel transition are available for purchase,<ref>{{cite web|title=iMac - Tech Specs - Apple|url=https://www.apple.com/imac/specs/|publisher=Apple Inc.|accessdate=July 28, 2015}}</ref> some technology-capable groups have developed software to install macOS on non-Apple computers. These are referred to as [[OSx86|Hackintoshes]], a [[portmanteau]] of the words "hack" and "Macintosh". This violates Apple's [[End-user license agreement|EULA]] (and is therefore unsupported by Apple technical support, warranties etc.), but communities that cater to personal users, who do not install for resale and profit, have generally been ignored by Apple.<ref>{{cite web|title=Home page – footer|url=http://www.tonymacx86.com/|website=tonymacx86.com|accessdate=July 28, 2015}}</ref><ref>{{cite web|last1=K|first1=M|title=Is installing Mavericks on Hackintosh legal?|url=https://apple.stackexchange.com/questions/107324/is-installing-mavericks-on-hackintosh-legal|website=apple.stackexchange.com|accessdate=July 28, 2015}}</ref><ref>{{cite web|title=Choosing the right CPU for your hackintosh|url=http://www.macbreaker.com/2012/07/choosing-right-cpu-for-your-hackintosh.html|website=www.macbreaker.com|accessdate=July 28, 2015}}</ref> These self-made computers allow more flexibility and customization of hardware, but at a cost of leaving the user more responsible for their own machine, such as on matter of data integrity or security.<ref>{{cite web|url=http://www.marco.org/2013/06/20/new-mac-pro-geekbench|title=Far Too Much Analysis Of The Alleged New Mac Pro Geekbench Score|website=Marco.org|last1=Arment|first1=Marco|accessdate=14 August 2015}}</ref> [[Psystar]], a business that attempted to profit from selling macOS on non-Apple certified hardware, was sued by Apple in 2008.<ref>{{cite web|last1=Taub|first1=Eric|title=Apple sues Psystar to block Macintosh clones|website=NYTimes.com|url=http://bits.blogs.nytimes.com/2008/07/16/apple-sues-psystar-to-block-macintosh-clone-sales/comment-page-2/?_r=0|publisher=New York Times|accessdate=1 August 2015}}</ref>

===PowerPC–Intel transition===
[[File:Steve Jobs Presentation 1.jpg|thumb|Steve Jobs talks about the transition to Intel processors]]
{{Main|Apple's transition to Intel processors}}
In April 2002, eWeek announced a rumor that Apple had a version of Mac OS X code-named [[Starvin' Marvin in Space|Marklar]], which ran on [[Intel x86]] processors. The idea behind Marklar was to keep Mac OS X running on an alternative platform should Apple become dissatisfied with the progress of the [[PowerPC]] platform.<ref>{{cite web | last=Rothenbourg | first=Matthew |author2=dePlume, Nick | url=http://www.eweek.com/c/a/Apple/Apple-Keeps-x86-Torch-Lit-with-Marklar/ | title=Apple Keeps x86 Torch Lit with 'Marklar' | accessdate=June 8, 2013 | date=August 30, 2002 | publisher=eWeek.com}}</ref> These rumors subsided until late in May 2005, when various media outlets, such as ''[[The Wall Street Journal]]''<ref>{{cite web | last1=Clark | first1=Don |last2=Wingfield | first2=Nick | url=https://www.wsj.com/articles/SB111680203134440188 | title = Apple Explores Use Of Chips From Intel For Macintosh Line | date=May 23, 2005 | work=[[The Wall Street Journal]] | publisher=[[Dow Jones & Company]] | accessdate=February 8, 2009}}</ref> and [[CNET]],<ref>{{cite web | last=Kanellos | first=Michael | url=http://www.news.com/2100-1006_3-5716696.html | title=Apple to Intel: Some advantage, lots of risk | accessdate=April 28, 2006 | date=May 23, 2005 | work=[[CNET]] | publisher=[[CBS Interactive]]}}</ref> announced that Apple would unveil Marklar in the coming months.<ref name="I'll See You Intel">{{cite web|last1=Gruber|first1=John|authorlink1=John Gruber|title=I'll See You Intel|url=http://daringfireball.net/2005/06/see_you_intel|website=Daring Fireball|accessdate=31 March 2016}}</ref><ref name="Intel-Apple Odds and Ends">{{cite web|last1=Gruber|first1=John|title=Intel-Apple Odds and Ends|url=http://daringfireball.net/2005/06/intel_apple_odds_and_ends|website=Daring Fireball|accessdate=31 March 2016}}</ref><ref name="Bombs Away">{{cite web|last1=Gruber|first1=John|title=Bombs Away|url=http://daringfireball.net/2005/06/bombs_away|website=Daring Fireball|accessdate=31 March 2016}}</ref>

On June 6, 2005, Steve Jobs announced in his keynote address at the annual Apple [[Worldwide Developers Conference]] that Apple would be making the transition from PowerPC to [[Intel]] processors over the following two years, and that Mac OS X would support both platforms during the transition. Jobs also confirmed rumors that Apple had versions of Mac OS X running on Intel processors for most of its developmental life. Intel-based Macs would run a new recompiled version of OS X along with [[Rosetta (software)|Rosetta]], a [[binary translation]] layer which enables software compiled for PowerPC Mac OS X to run on Intel Mac OS X machines.<ref name="John Siracusa mourns the Power PC">{{cite web|last1=Siracusa|first1=John|title=Picking up the pieces: John Siracusa mourns the Power PC|url=https://arstechnica.com/apple/2005/06/mac-20050607/|website=[[Ars Technica]]|accessdate=31 March 2016}}</ref> The system was included with Mac OS X versions up to version 10.6.8.<ref name="AppleInsider: Mac OS X Lion drops Front Row, Java runtime, Rosetta">{{cite web |url=http://www.appleinsider.com/articles/11/02/26/mac_os_x_lion_drops_front_row_java_runtime_rosetta.html |title=Mac OS X Lion drops Front Row, Java runtime, Rosetta |author=AppleInsider Staff |date=February 26, 2011 |work=[[AppleInsider]] |publisher=AppleInsider, Inc |accessdate=February 27, 2011| archiveurl = https://web.archive.org/web/20110301003419/http://www.appleinsider.com/articles/11/02/26/mac_os_x_lion_drops_front_row_java_runtime_rosetta.html | archivedate=March 1, 2011| deadurl=no}}</ref> Apple dropped support for Classic mode on the new Intel Macs. Third party emulation software such as [[Mini vMac]], [[Basilisk II]] and [[SheepShaver]] provided support for some early versions of Mac OS. A new version of Xcode and the underlying command-line compilers supported building [[universal binary|universal binaries]] that would run on either architecture.<ref>{{cite press release | url=https://www.apple.com/pr/library/2005/jun/06intel.html | accessdate=April 8, 2006 | title=Apple to Use Intel Microprocessors Beginning in 2006 | publisher=[[Apple Inc.|Apple]] | date=June 6, 2005}}</ref>

PowerPC-only software is supported with Apple's official emulation software, [[Rosetta (software)|Rosetta]], though applications eventually had to be rewritten to run properly on the newer versions released for Intel processors. Apple initially encouraged developers to produce universal binaries with support for both PowerPC and Intel.<ref>{{cite web | title=Adopting Universal Binaries | accessdate=December 20, 2006 | date=January 2006 | url=https://developer.apple.com/macosx/adoptinguniversalbinaries.html|publisher=[[Apple Inc.|Apple]]}}</ref> There is a performance penalty when PowerPC binaries run on Intel Macs through Rosetta. Moreover, some PowerPC software, such as kernel extensions and System Preferences plugins, are not supported on Intel Macs at all. Some PowerPC applications would not run on macOS at all. Plugins for Safari need to be compiled for the same platform as Safari, so when Safari is running on Intel, it requires plug-ins that have been compiled as Intel-only or universal binaries, so PowerPC-only plug-ins will not work.<ref>{{cite web | last=Landau | first=Ted | title=OS X First Aid | url=http://www.macworld.com/article/50339/2006/04/firstaidintel.html | work=[[Macworld]] | publisher=[[International Data Group|IDG]] | date=May 2006 | accessdate=February 8, 2009}}</ref> While Intel Macs are able to run PowerPC, Intel, and universal binaries; PowerPC Macs support only universal and PowerPC builds.

Support for the PowerPC platform was dropped following the transition. In 2009, Apple announced at its [[Worldwide Developers Conference]] that Mac OS X 10.6 Snow Leopard would drop support for PowerPC processors and be Intel-only.<ref>{{cite web | last=Stevens | first=Tim | title=Snow Leopard officially puts PowerPC Macs on endangered species list | url=https://www.engadget.com/2009/06/10/snow-leopard-officially-puts-powerpc-macs-on-endangered-species/ | work=[[Engadget]] |publisher=[[AOL]] | date=June 10, 2009 | accessdate=June 15, 2009}}</ref> Rosetta continued to be offered as an optional download or installation choice in Snow Leopard before it was discontinued with Mac OS X 10.7 Lion.<ref name="MacRumors: Mac OS X Lion: Drops PowerPC Emulation, Adds QuickTime Pro Features, Much More">{{cite web |url=http://www.macrumors.com/2011/02/27/mac-os-x-lion-drops-powerpc-emulation-adds-quicktime-pro-features-much-more/ |title=Mac OS X Lion: Drops PowerPC Emulation, Adds QuickTime Pro Features, Much More |author=Arnold Kim |date=February 27, 2011 |publisher=[[MacRumors]] |accessdate=February 27, 2011}}</ref><ref name="MacRumors: Mac OS X Lion: Drops PowerPC Emulation, Adds QuickTime Pro Features, Much More" /> In addition, new versions of Mac OS X first- and third-party software increasingly required Intel processors, including new versions of iLife, iWork, Aperture and Logic Pro.

==Features==

===Aqua user interface===
{{Main|Aqua (user interface)}}
[[File:Macosxpb.png|thumb|250px|The original [[Aqua (user interface)|Aqua]] user interface as seen in the [[Mac OS X Public Beta]] from 2000]]

One of the major differences between the [[classic Mac OS]] and the current macOS was the addition of [[Aqua (user interface)|Aqua]], a graphical user interface with water-like elements, in the first major release of Mac OS X. Every window element, text, graphic, or [[widget (computing)|widget]] is drawn on-screen using [[spatial anti-aliasing]] technology.<ref>{{cite web |url=https://developer.apple.com/documentation/UserExperience/Conceptual/AppleHIGuidelines/XHIGPartIII/chapter_11_section_1.html | publisher=[[Apple Inc.|Apple]] | accessdate=December 16, 2008 | date=June 9, 2008 | work=Apple Human Interface Guidelines | title=The Aqua Interface |archiveurl=https://web.archive.org/web/20081209044209/http://developer.apple.com/documentation/UserExperience/Conceptual/AppleHIGuidelines/XHIGPartIII/chapter_11_section_1.html | archivedate=December 9, 2008}}</ref> [[ColorSync]], a technology introduced many years before, was improved and built into the core drawing engine, to provide color matching for [[printing]] and [[multimedia]] professionals.<ref name="davidson">{{cite book | title=Learning Cocoa With Objective-C | page=6 | last=Davidson | first=James Duncan | publisher=O'Reilly | year=2002 | isbn=0-596-00301-3}}</ref> Also, [[drop shadow]]s were added around windows and isolated text elements to provide a sense of depth. New interface elements were integrated, including sheets ([[dialog box]]es attached to specific windows) and drawers, which would slide out and provide options.

The use of soft edges, translucent colors, and pinstripes, similar to the hardware design of the first [[iMac]]s, brought more texture and color to the user interface when compared to what [[Mac OS 9]] and [[Mac OS X Server 1.0]]'s "[[Platinum (theme)|Platinum]]" appearance had offered. According to John Siracusa, an editor of [[Ars Technica]], the introduction of Aqua and its departure from the then conventional look "hit like a ton of bricks."<ref>{{cite web | last=Siracusa | first=John | url=https://arstechnica.com/reviews/os/mac-os-x-10-5.ars/3 | title=Mac OS X 10.5 Leopard: the Ars Technica review | publisher=[[Condé Nast Publishing|Condé Nast Digital]] | work=[[Ars Technica]] | accessdate=December 16, 2008 | date=October 28, 2007}}</ref>
[[Bruce Tognazzini]] (who founded the original Apple Human Interface Group) said that the Aqua interface in [[Mac OS X 10.0]] represented a step backwards in usability compared with the original Mac OS interface.<ref>{{cite web |date=February 2000 | first=Bruce | last=Tognazzini | url=http://www.asktog.com/columns/034OSX-FirstLook.html | title=OS X: A First Look | accessdate=November 5, 2008}}</ref><ref>{{cite web | date=February 16, 2004 | first=Matthew Paul | last=Thomas | url=http://mpt.net.nz/archive/2004/02/16/os-x | archiveurl=https://web.archive.org/web/20081014095216/http://mpt.net.nz/archive/2004/02/16/os-x | archivedate=October 14, 2008 |title=My first 48 hours enduring Mac OS X | accessdate=November 5, 2008}}</ref>
Third-party developers started producing [[skin (computing)|skins]] for customizable applications and other operating systems which mimicked the Aqua appearance. To some extent, Apple has used the successful transition to this new design as leverage, at various times threatening [[legal action]] against people who make or distribute software with an interface the company says is derived from its [[copyright]]ed design.<ref>{{cite web|title=Apple lowers boom on Aqua 'skins' |date=February 2, 2001 |url=http://www.zdnet.com/zdnn/stories/newsbursts/0,7407,2681914,00.html?chkpt=p1bn |archiveurl=https://web.archive.org/web/20011031104835/http://www.zdnet.com/zdnn/stories/newsbursts/0%2C7407%2C2681914%2C00.html?chkpt=p1bn |archivedate=October 31, 2001 |accessdate=May 22, 2006 |work=[[ZDNet]] |publisher=[[CBS Interactive]] |deadurl=yes |df= }}</ref>

Apple has continued to change aspects of the macOS appearance and design, particularly with tweaks to the appearance of windows and the menu bar. Since 2012, Apple has sold many of its Mac models with high-resolution [[Retina display]]s, and macOS and its [[Application programming interface|APIs]] have extensive support for resolution-independent development on supporting high-resolution displays. Reviewers have described Apple's support for the technology as superior to that on Windows.<ref>{{cite web|last1=Castle|first1=Alex|title=How to make the Windows desktop look good on high-DPI displays|url=http://www.pcworld.com/article/2098586/how-to-make-the-windows-desktop-look-good-on-high-dpi-displays.html|website=PC World|accessdate=9 July 2015}}</ref><ref>{{cite web|last1=Cunningham|first1=Andrew|title=Using the Retina MacBook as a Windows PC|url=https://arstechnica.com/apple/2015/04/using-the-retina-macbook-as-a-windows-pc/|website=Ars Technica|accessdate=9 July 2015}}</ref><ref>{{cite web|last1=Hutchinson|first1=Lee|title=The Retina iMac and its 5K display… as a gaming machine? [Updated]|url=https://arstechnica.com/apple/2014/10/the-retina-imac-and-its-5k-display-as-a-gaming-machine/2/|website=Ars Technica|accessdate=9 July 2015}}</ref>

The [[human interface guidelines]] published by Apple for macOS are followed by many applications, giving them consistent user interface and keyboard shortcuts.<ref>{{cite book | title=Programming Mac OS X: A Guide for Unix Developers | year=2003 | publisher=Manning | isbn=1-930110-85-5 | last=O'Malley | first=Kevin | page=7}}</ref> In addition, new services for applications are included, which include spelling and grammar checkers, special characters palette, color picker, font chooser and dictionary; these global features are present in every Cocoa application, adding consistency. The graphics system [[OpenGL]] composites windows onto the screen to allow hardware-accelerated drawing. This technology, introduced in version 10.2, is called [[Quartz Compositor|Quartz Extreme]], a component of [[Quartz (graphics layer)|Quartz]]. Quartz's internal imaging model correlates well with the [[Portable Document Format]] (PDF) imaging model, making it easy to output PDF to multiple devices.<ref name="davidson" /> As a side result, PDF viewing and creating PDF documents from any application are built-in features.<ref>{{cite web | url=https://www.apple.com/macosx/what-is-macosx/ | publisher=[[Apple Inc.|Apple]] | accessdate=March 2, 2011 | title=OS X. It's what makes a Mac a Mac.}}</ref> Reflecting its popularity with design users, macOS also has system support for a variety of professional video and image formats and includes an extensive pre-installed font library, featuring many prominent brand-name designs.<ref name="Making the ultimate creative content OS from bits of Windows, Mac, and Linux">{{cite web|last1=Girard|first1=Dave|title=Making the ultimate creative content OS from bits of Windows, Mac, and Linux|url=https://arstechnica.com/information-technology/2013/09/making-the-ultimate-creative-content-os-ubercreate-os-1-0/|website=Ars Technica|accessdate=14 August 2015}}</ref>

===Components===
{{Main|List of macOS components}}

The [[Finder (software)|Finder]] is a file browser allowing quick access to all areas of the computer, which has been modified throughout subsequent releases of macOS.<ref>{{cite web | first=Thom | last=Holwerda | url=http://www.osnews.com/story/18992/Review_Mac_OS_X_10_5_Leopard/page2/ | accessdate=April 15, 2009 | date=December 6, 2007 | title=Review: Mac OS X 10.5 Leopard | publisher=OS News | quote=The next area where Apple claims to have made major improvements is the Finder.}}</ref><ref>{{cite web | first=John | last=Siracusa | accessdate=April 15, 2009 | date=January 26, 2006 | title=Finding Leopard | url=https://arstechnica.com/staff/fatbits/2006/01/2673.ars | publisher=[[Condé Nast Publishing|Condé Nast Digital]] | work=[[Ars Technica]] | quote=Unsurprisingly, each new Mac OS X release has been the vehicle for a parade of Finder fantasies.}}</ref> [[Quick Look]] is part of the Finder since [[Mac OS X Leopard|version 10.5]]. It allows for dynamic previews of files, including videos and multi-page documents without opening any other applications. [[Spotlight (software)|Spotlight]], a file searching technology which has been integrated into the Finder since [[Mac OS X Tiger|version 10.4]], allows rapid real-time searches of data files; mail messages; photos; and other information based on item properties (metadata) and/or content.<ref>{{cite web | url=https://arstechnica.com/apple/reviews/2005/04/macosx-10-4.ars/9 | first=John | last=Siracusa | title=Mac OS X 10.4 Tiger | accessdate=April 15, 2009 | publisher=[[Condé Nast Publishing|Condé Nast Digital]] | work=[[Ars Technica]] | date=April 28, 2005}}</ref><ref>{{cite web | title=Mac 101: Spotlight | url=http://support.apple.com/kb/HT2531 | publisher=[[Apple Inc.|Apple]] | date=November 6, 2008 | accessdate=April 15, 2009}}</ref> macOS makes use of a [[Dock (Mac OS X)|Dock]], which holds file and folder shortcuts as well as minimized windows.

Apple added "Exposé" in [[Mac OS X Panther|version 10.3]] (called [[Mission Control (macOS)|Mission Control]] since [[Mac OS X Lion|version 10.7]]), a feature which includes three functions to help accessibility between windows and desktop. Its functions are to instantly display all open windows as thumbnails for easy navigation to different tasks, display all open windows as thumbnails from the current application, and hide all windows to access the desktop.<ref>{{cite web | url=http://support.apple.com/kb/HT2503 | publisher=[[Apple Inc.|Apple]]|accessdate=December 16, 2008 | date=October 31, 2008 | title=Mac 101: Exposé}}</ref> Also, [[FileVault]] was introduced, which is an optional encryption of the user's files with the 128-bit [[Advanced Encryption Standard]] (AES-128).<ref>{{cite web | url=http://docs.info.apple.com/article.html?path=Mac/10.5/en/8727.html | publisher=[[Apple Inc.|Apple]] | accessdate=December 16, 2008 | title=About FileVault | work=Mac OS X 10.5 Help}}</ref>

Features introduced in [[Mac OS X Tiger|version 10.4]] include [[Automator (software)|Automator]], an application designed to create an automatic workflow for different tasks;<ref>{{cite web | url=http://support.apple.com/kb/HT2488 | title=Mac 101: Automator | date=November 6, 2008 | accessdate=December 16, 2008 | publisher=[[Apple Inc.|Apple]]}}</ref> [[Dashboard (Mac OS)|Dashboard]], a full-screen group of small applications called [[desktop widget]]s that can be called up and dismissed in one keystroke;<ref>{{cite web | url=http://support.apple.com/kb/HT2492 | title=Mac 101: Dashboard | date=November 11, 2008 | accessdate=December 16, 2008 | publisher=[[Apple Inc.|Apple]]}}</ref> and [[Front Row (software)|Front Row]], a media viewer interface accessed by the [[Apple Remote]].<ref>{{cite web | url=https://www.apple.com/macosx/features/300.html#frontrow | publisher=[[Apple Inc.|Apple]] | accessdate=December 16, 2008 | title=Front Row | archiveurl=https://web.archive.org/web/20081215210759/http://www.apple.com/macosx/features/300.html#frontrow | archivedate=December 15, 2008}}</ref> Moreover, the Sync Services were included, which is a system that allows applications to access a centralized extensible database for various elements of user data, including calendar and contact items. The operating system then managed conflicting edits and data consistency.<ref>{{cite web | url=https://developer.apple.com/documentation/Cocoa/Conceptual/SyncServices/Articles/WhySyncServices.html | publisher=[[Apple Inc.|Apple]] | accessdate=December 16, 2008 | date=October 31, 2007 | title=Why Use Sync Services? |archiveurl=https://web.archive.org/web/20081012141434/http://developer.apple.com/documentation/Cocoa/Conceptual/SyncServices/Articles/WhySyncServices.html | archivedate=October 12, 2008}}</ref>

All system icons are scalable up to 512×512 pixels as of [[Mac OS X Leopard|version 10.5]] to accommodate various places where they appear in larger size, including for example the [[Cover Flow]] view, a [[3D computer graphics|three-dimensional]] graphical user interface included with [[iTunes]], the Finder, and other Apple products for visually skimming through files and digital media libraries via cover artwork. That version also introduced [[Spaces (software)|Spaces]], a [[virtual desktop]] implementation which enables the user to have more than one desktop and display them in an Exposé-like interface;<ref>{{cite web | url=https://www.apple.com/macosx/features/spaces.html | accessdate=December 16, 2008 | title=Spaces. Room for everything. | publisher=[[Apple Inc.|Apple]] |archiveurl=https://web.archive.org/web/20081215205127/http://www.apple.com/macosx/features/spaces.html | archivedate=December 15, 2008}}</ref> an automatic backup technology called [[Time Machine (Apple software)|Time Machine]], which provides the ability to view and restore previous versions of files and application data;<ref>{{cite web | url=https://www.apple.com/macosx/features/timemachine.html | accessdate=December 16, 2008 | title=Time Machine. A giant leap backward. | publisher=[[Apple Inc.|Apple]]}}</ref> and [[Screen Sharing]] was built in for the first time.<ref>{{cite web | url=https://www.apple.com/macosx/features/300.html#finder | accessdate=December 16, 2008 | title=Finder | publisher=[[Apple Inc.|Apple]] |archiveurl=https://web.archive.org/web/20081215210759/http://www.apple.com/macosx/features/300.html | archivedate=December 15, 2008}}</ref>

In more recent releases, Apple has developed support for [[emoji]] characters by including the proprietary [[Apple Color Emoji]] font.<ref>{{cite web|url=https://www.theverge.com/2013/3/4/3966140/how-emoji-conquered-the-world|accessdate=2014-07-28|title=How emoji conquered the world|author=Jeff Blagdon|publisher=The Verge|date=2013-03-04}}</ref><ref name="Smile, You’re Speaking EMOJI: the rapid evolution of a wordless tongue">{{cite web|last1=Sternbergh|first1=Adam|title=Smile, You’re Speaking EMOJI: the rapid evolution of a wordless tongue|url=http://nymag.com/daily/intelligencer/2014/11/emojis-rapid-evolution.html|website=New York magazine|accessdate=15 August 2015}}</ref> Apple has also connected macOS with social networks such as [[Twitter]] and [[Facebook]] through the addition of share buttons for content such as pictures and text.<ref>{{cite web|title=OS X Mountain Lion: Share with iCloud, Facebook, Twitter, and other services|url=https://support.apple.com/kb/PH11435?locale=en_US|publisher=Apple|accessdate=14 August 2015}}</ref>  Apple has brought several applications and features that originally debuted in [[iOS]], its mobile operating system, to macOS in recent releases, notably the [[intelligent personal assistant]] [[Siri]], which was introduced in [[macOS Sierra|version 10.12]] of macOS.<ref name="siri1">{{cite web | url=http://fieldguide.gizmodo.com/13-things-you-can-do-with-macos-sierra-you-couldnt-befo-1787059614 | accessdate=September 28, 2016 | title=13 Things You Can Do with MacOS Sierra You Couldn't Before | publisher=[[Gizmodo]]}}</ref><ref name="siri2">{{cite web | url=http://www.macworld.com/article/3088224/macs/how-to-use-siri-on-macos-sierra.html | accessdate=September 28, 2016 | title=How to use Siri in macOS Sierra: A look at using the Apple's virtual assistant on the Mac | publisher=[[Macworld]]}}</ref>

===Multilingual support===
There are 34 system languages available in macOS for the user at the moment of installation; the system language is used throughout the entire operating system environment.<ref name="macoslanguages" /> Input methods for typing in dozens of scripts can be chosen independently of the system language.<ref name="languages">{{cite web|title=System – New system languages. |url=https://www.apple.com/macosx/whats-new/features.html#system |publisher=[[Apple Inc.|Apple]] |accessdate=June 6, 2011 |deadurl=yes |archiveurl=https://web.archive.org/web/20110623030050/http://www.apple.com/macosx/whats-new/features.html |archivedate=June 23, 2011 |df= }}</ref> Recent updates have added increasing support for [[Chinese characters]] and interconnections with popular social networks in [[China]].<ref name="Apple’s Tim Cook visits China to talk expansion, expansion, expansion">{{cite web|last1=Cheng|first1=Jacqui|title=Apple’s Tim Cook visits China to talk expansion, expansion, expansion|url=https://arstechnica.com/apple/2013/01/apples-tim-cook-visits-china-to-talk-expansion-expansion-expansion/|website=Ars Technica|accessdate=14 August 2015}}</ref><ref name="Next version of OS X to be more iOS-like than ever with Mountain Lion">{{cite web|last1=Foresman|first1=Chris|title=Next version of OS X to be more iOS-like than ever with Mountain Lion|url=https://arstechnica.com/apple/2012/02/apple-unleashes-mountain-lion-on-developers-set-for-summer-release/|website=Ars Technica|publisher=Conde Nast|accessdate=14 August 2015}}</ref><ref name="Apple targets China, Japan with new OS X El Capitan system fonts and input">{{cite web|last1=Campbell|first1=Mikey|title=Apple targets China, Japan with new OS X El Capitan system fonts and input|url=http://appleinsider.com/articles/15/06/08/apple-targets-china-japan-with-new-os-x-el-capitan-system-fonts-and-input|website=Apple Insider|accessdate=14 August 2015}}</ref><ref name="chinamtnlion">{{cite web | url=http://thenextweb.com/apple/2012/02/16/apple-is-serious-about-china-sina-weibo-baidu-youku-and-more-integrated-into-mountain-lion/ | title=Apple courts China with Sina Weibo, Baidu, Youku and more integrated in Mountain Lion | publisher=The Next Web | date=February 16, 2012 | accessdate=March 15, 2012 | author=Panzarino, Matthew}}</ref>

===Updating methods===
{{Anchor|Functionality|Software Update}}

macOS can be updated using the [[Mac App Store]] application<ref>{{Cite book|url=https://books.google.com/books?id=9uukAgAAQBAJ&pg=PA22&dq=OS+X+can+be+updated+using+mac+app+store&hl=en&sa=X&ved=0ahUKEwiF29iNiPzTAhUH2GMKHVa9B_AQ6AEIIjAA#v=onepage&q=OS%20X%20can%20be%20updated%20using%20mac%20app%20store&f=false|title=Total OS X Mavericks Superguide: Everything you need to know about Apple's newest operating system|last=Editors|first=Macworld|date=2014-01-22|publisher=IDG Consumer & SMB, Inc.|isbn=9781937821388|language=en}}</ref> or the <code>softwareupdate</code> [[command line]] utility.  Until [[OS X Mountain Lion|OS X 10.8 Mountain Lion]], a separate [[List of macOS components#Software Update|Software Update]] application performed this functionality. In Mountain Lion and later, this was merged into the Mac App Store application, although the underlying update mechanism remains unchanged and is fundamentally different than the download mechanism used when purchasing an App Store application.

==Release history==
{{Main|History of macOS#Releases}}

<imagemap>
File:Osxboxes.png|thumb|center|747px|Box/Mac App Store artwork for every version of macOS. Left to right: [[Mac OS X v10.0|Cheetah]]/[[Mac OS X v10.1|Puma]] (1), [[Mac OS X v10.2|Jaguar]] (2), [[Mac OS X v10.3|Panther]] (3), [[Mac OS X v10.4|Tiger]] (4), [[Mac OS X v10.5|Leopard]] (5), [[Mac OS X v10.6|Snow Leopard]] (6), [[Mac OS X v10.7|Lion]] (7), [[OS X v10.8|Mountain Lion]] (8), [[OS X v10.9|Mavericks]] (9), [[OS X v10.10|Yosemite]] (10), [[OS X v10.11|El Capitan]] (11), [[macOS Sierra|Sierra]] (12).

rect 3 1 4 4 60 71 [[Mac OS X v10.0]]
rect 64 4 4 4 127 72 [[Mac OS X v10.2]]
rect 131 4 4 2 194 71 [[Mac OS X Panther]]
rect 196 4 4 2 256 72 [[Mac OS X Tiger]]
rect 260 4 4 2 317 75 [[Mac OS X Leopard]]
rect 318 4 4 3 375 75 [[Mac OS X Snow Leopard]]
rect 378 4 4 2 434 76 [[Mac OS X Lion]]
rect 437 4 4 4 497 76 [[OS X Mountain Lion]]
rect 500 4 4 4 557 76 [[OS X Mavericks]]
rect 563 4 4 4 618 76 [[OS X Yosemite]]
rect 626 4 4 4 681 76 [[OS X El Capitan]]
rect 687 4 4 4 743 76 [[macOS Sierra]]

desc bottom-left
</imagemap>
{| class="wikitable"
|+ Mac OS X, OS X, and macOS version information
|-
! Version
! Codename
! Darwin version
! Processor support
! Application support
! Kernel
! Date announced
! Release date
! Most recent version
|-
| [[Rhapsody (operating system)|Rhapsody]] Developer Release
| Grail1Z4 /  Titan1U
|
| rowspan="6" | 32-bit PowerPC
| rowspan="8" | 32-bit PowerPC
| rowspan="10" | 32-bit
| {{unknown}}
| August 31, 1997
| DR2 (May 14, 1998)
|-
| [[Mac OS X Server 1.0]]
| Hera
|
| {{unknown}}
| March 16, 1999
| 1.2v3 (October 27, 2000)
|-
| Mac OS X Developer Preview
| {{unknown}}
|
| May 11, 1998<ref>{{cite news |url=http://news.cnet.com/OS-X-is-the-future-for-Apple/2100-1001_3-211065.html |title=OS X is the future for Apple |author=Davis, Jim |date=May 11, 1998 |accessdate=July 17, 2013 |publisher=[[CNET]]}}</ref>
| March 16, 1999
| DP4 (April 5, 2000)
|-
| [[Mac OS X Public Beta]]
| Kodiak<ref>{{cite web|url=http://www.networkworld.com/article/2869105/software/kodiak-to-lion--10-years-of-mac-os-x.html|title=Kodiak to Lion: 10 years of Mac OS X|author=Steven Borden-Weill|date=April 15, 2011|publisher=[[Network World]]}}</ref>
| 1.2.1
| {{unknown}}
| September 13, 2000
| {{n/a}}
|-
| [[Mac OS X 10.0]]
| Cheetah
| 1.3.1
| {{unknown}}
| March 24, 2001
| 10.0.4 (June 22, 2001)
|-
| [[Mac OS X 10.1]]
| Puma
| 1.4.1 / 5
| July 18, 2001<ref>{{cite press release | url=https://www.apple.com/pr/library/2001/jul/18macosx.html | title=Apple Previews Next Version of Mac OS X | publisher=[[Apple Inc.|Apple]] | date=July 18, 2001 | accessdate=March 11, 2010}}</ref>
| September 25, 2001
| 10.1.5 (June 6, 2002)
|-
| [[Mac OS X 10.2]]
| Jaguar
| 6
| 32/64-bit PowerPC{{ref label|g5jaguar|Note 1|none}}
| May 6, 2002<ref>{{cite press release | url=https://www.apple.com/pr/library/2002/may/06jaguar.html | title=Apple Previews "Jaguar", the Next Major Release of Mac OS X | publisher=[[Apple Inc.|Apple]] | date=May 6, 2002 | accessdate=March 11, 2010}}</ref>
| August 24, 2002
| 10.2.8 (October 3, 2003)
|-
| [[Mac OS X Panther|Mac OS X 10.3]]
| Panther
| 7
| 32/64-bit PowerPC
| June 23, 2003<ref>{{cite press release | url=https://www.apple.com/pr/library/2003/jun/23panther.html | title=Apple Previews Mac OS X "Panther" | publisher=[[Apple Inc.|Apple]] | date=June 23, 2003 | accessdate=March 11, 2010}}</ref>
| October 24, 2003
| 10.3.9 (April 15, 2005)
|-
| [[Mac OS X Tiger|Mac OS X 10.4]]
| Tiger
| 8
| rowspan="2" | 32/64-bit PowerPC and Intel
| 32/64-bit{{ref label|tiger64bitcli|Note 2|none}} PowerPC{{ref label|rosetta|Note 3|none}} and Intel
| May 4, 2004<ref>{{cite press release | url=https://www.apple.com/pr/library/2004/may/04wwdc.html | title=Steve Jobs to Kick Off Apple's Worldwide Developers Conference 2004 with Preview of Mac OS X "Tiger" | publisher=[[Apple Inc.|Apple]] | accessdate=March 11, 2010}}</ref>
| April 29, 2005
| 10.4.11 (November 14, 2007)
|-
| [[Mac OS X Leopard|Mac OS X 10.5]]
| Leopard
| 9
| 32/64-bit PowerPC{{ref label|rosetta|Note 3|none}} and Intel
| June 26, 2006<ref>{{cite press release | url=https://www.apple.com/pr/library/2006/jun/26wwdc.html | title=Apple Executives to Preview Mac OS X "Leopard" at WWDC 2006 Keynote | publisher=[[Apple Inc.|Apple]] | accessdate=March 11, 2010}}</ref>
| October 26, 2007
| 10.5.8 (August 5, 2009)
|-
| [[Mac OS X Snow Leopard|Mac OS X 10.6]]
| Snow Leopard
| 10
| 32/64-bit Intel
| 32/64-bit Intel<br />32-bit PowerPC{{ref label|rosetta|Note 3|none}}
| rowspan="2" | 32/64-bit<ref>{{cite web|title=Road to Mac OS X Snow Leopard: 64-bit to the Kernel|url=http://appleinsider.com/articles/08/10/28/road_to_mac_os_x_snow_leopard_64_bit_to_the_kernel|publisher=AppleInsider|accessdate=September 28, 2015|date=October 28, 2008}}</ref>
| June 9, 2008<ref>{{cite press release | url=https://www.apple.com/pr/library/2008/06/09snowleopard.html | title=Apple Previews Mac OS X Snow Leopard to Developers | publisher=[[Apple Inc.|Apple]] | date=June 9, 2008 | accessdate=March 11, 2010}}</ref>
| August 28, 2009
| 10.6.8 v1.1 (July 25, 2011)
|-
| [[Mac OS X Lion|Mac OS X 10.7]]
| Lion
| 11
| rowspan="7" | 64-bit Intel
| rowspan="7" | 32/64-bit Intel
| October 20, 2010<ref>{{cite press release | url=https://www.apple.com/pr/library/2010/10/20lion.html | title=Apple Gives Sneak Peek of Mac OS X Lion | publisher=[[Apple Inc.|Apple]] | date=October 20, 2010 | accessdate=October 20, 2010}}</ref>
| July 20, 2011
| 10.7.5 (September 19, 2012)
|-
| [[OS X Mountain Lion|OS X 10.8]]
| Mountain Lion
| 12
| rowspan="6" | 64-bit<ref>{{cite web|title=Older 64-bit Macs out of the picture for Mountain Lion|url=http://www.cnet.com/news/older-64-bit-macs-out-of-the-picture-for-mountain-lion/|publisher=CNET|accessdate=September 28, 2015|date=July 11, 2012}}</ref>
| February 16, 2012<ref name="PR-16-02">{{cite press release | url=https://www.apple.com/pr/library/2012/02/16Apple-Releases-OS-X-Mountain-Lion-Developer-Preview-with-Over-100-New-Features.html | title=Apple Releases OS X Mountain Lion Developer Preview with Over 100 New Features | publisher=[[Apple Inc.|Apple]] | date=February 16, 2012 | accessdate=February 16, 2012}}</ref>
|July 25, 2012<ref name="PR-25-07">{{cite press release | url=https://images.apple.com/pr/library/2012/07/25Mountain-Lion-Available-Today-From-the-Mac-App-Store.html | title=Mountain Lion Available Today From Mac App Store | publisher=[[Apple Inc.|Apple]] | date=July 25, 2012 | accessdate=July 25, 2012}}</ref>
|10.8.5 (12F45) (October 3, 2013)
|-
| [[OS X Mavericks|OS X 10.9]]
| Mavericks
| 13
| June 10, 2013<ref>{{cite press release | url=https://www.apple.com/pr/library/2013/06/10Apple-Releases-Developer-Preview-of-OS-X-Mavericks-With-More-Than-200-New-Features.html| title=Apple Releases Developer Preview of OS X Mavericks With More Than 200 New Features| publisher=[[Apple Inc.|Apple]] | date=June 10, 2013 | accessdate=February 24, 2015}}</ref>
|October 22, 2013
|10.9.5 (13F1112) (September 18, 2014)<ref>{{cite web|url=http://appleinsider.com/articles/14/09/17/apple-releases-os-x-1095-mavericks-with-reliability-enhancements-includes-safari-706|title=Apple releases OS X 10.9 Mavericks with reliability enhancements, includes Safari 7.0.6|publisher=appleinsider}} Retrieved on December 18, 2014.</ref>
|-
| [[OS X Yosemite|OS X 10.10]]
| Yosemite
| 14
| June 2, 2014<ref>{{cite press release | url=https://www.apple.com/pr/library/2014/06/02Apple-Announces-OS-X-Yosemite.html| title=Apple Announces OS X Yosemite| publisher=[[Apple Inc.|Apple]] | date=June 2, 2014 | accessdate=February 24, 2015}}</ref>
|October 16, 2014
|10.10.5 (14F27) (August 13, 2015)
|-
| [[OS X El Capitan|OS X 10.11]]
| El Capitan
| 15
| June 8, 2015<ref>{{cite press release | url=https://www.apple.com/pr/library/2015/06/08Apple-Announces-OS-X-El-Capitan-with-Refined-Experience-Improved-Performance.html| title =Apple Announces OS X El Capitan| publisher=[[Apple Inc.|Apple]] | date=June 8, 2015 | accessdate=June 8, 2015}}</ref>
|September 30, 2015
|10.11.6 (15G31) (July 18, 2016)
|-
| [[macOS Sierra|macOS 10.12]]
| Sierra
| 16
| June 13, 2016<ref>{{cite press release|url=https://www.apple.com/newsroom/2016/06/apple-previews-major-update-with-macos-sierra.html |title=Apple previews major update with macOS Sierra |publisher=Apple |date=June 13, 2016 |accessdate=June 13, 2016}}</ref>
| September 20, 2016
| 10.12.6 (16G29) (July 19, 2017)
|-
| [[macOS High Sierra|macOS 10.13]]
| High Sierra
| 17
| June 5, 2017
| September 25, 2017
| 10.13.0 (17A365) (September 25, 2017)
|}

[[File:Mac_OS_X_Timeline_of_Versions.png|thumb|450px|[[Timeline]] of versions (not including 2016's macOS Sierra and 2017's High Sierra)]]

:{{note label|g5jaguar||Note 1}}The [[PowerMac G5]] had special Jaguar builds.
:{{note label|tiger64bitcli||Note 2}}Tiger did not support 64-bit GUI applications, only 64-bit CLI applications.
:{{note label|rosetta||Note 3}}32-bit PowerPC applications were supported on Intel processors with [[Rosetta (software)|Rosetta]].

With the exception of [[Mac OS X Server 1.0]] and the original public beta, OS X versions were named after [[big cat]]s until [[OS X Mavericks|OS X 10.9 Mavericks]], when Apple switched to using [[California]] locations. Prior to its release, [[Mac OS X v10.0|Mac OS X 10.0]] was [[code name]]d "Cheetah" internally at Apple, and [[Mac OS X v10.1|Mac OS X 10.1]] was code named internally as "Puma". After the immense buzz surrounding [[Mac OS X v10.2|Mac OS X 10.2]], codenamed "Jaguar", Apple's product marketing began openly using the code names to promote the operating system. [[Mac OS X Panther|Mac OS X 10.3]] was marketed as "Panther", [[Mac OS X Tiger|Mac OS X 10.4]] as "Tiger", [[Mac OS X Leopard|Mac OS X 10.5]] as "Leopard", [[Mac OS X Snow Leopard|Mac OS X 10.6]] as "Snow Leopard", [[Mac OS X Lion|Mac OS X 10.7]] as "Lion", [[OS X Mountain Lion|OS X 10.8]] as "Mountain Lion", and [[OS X Mavericks|OS X 10.9]] as "Mavericks".

"Panther", "Tiger" and "Leopard" are registered as trademarks of Apple,<ref>{{US trademark|78257226}}</ref><ref>{{US trademark|78269988}}</ref><ref>{{US trademark|78270003}}</ref> but "Cheetah", "Puma" and "Jaguar" have never been registered. Apple has also registered "Lynx" and "Cougar" as trademarks, though these were allowed to lapse.<ref>{{US trademark|78271630}}</ref><ref>{{US trademark|78271639}}</ref> Computer retailer [[Tiger Direct]] sued Apple for its use of the name "Tiger". On May 16, 2005 a US federal court in the Southern District of Florida ruled that Apple's use did not infringe on Tiger Direct's trademark.<ref>{{cite web | first=Jade | last=Kasper | title=Court sides with Apple over "Tiger" trademark dispute | url=http://www.appleinsider.com/articles/05/05/13/court_sides_with_apple_over_tiger_trademark_dispute.html | publisher=[[AppleInsider]] | accessdate=April 25, 2006}}</ref>

===Mac OS X Public Beta===
{{Main|Mac OS X Public Beta}}

On September 13, 2000, Apple released a $29.95<ref>{{cite web | author=John Siracusa | url=https://arstechnica.com/reviews/4q00/macosx-pb1/macos-x-beta-1.html | title=Mac OS X Beta&nbsp;– Page 1 – (10/2000) | publisher=[[Condé Nast Publishing|Condé Nast Digital]] | work=[[Ars Technica]] | accessdate=March 11, 2010}}</ref> "preview" version of Mac OS X internally codenamed Kodiak in order to gain feedback from users.

The "PB" as it was known marked the first public availability of the Aqua interface and Apple made many changes to the UI based on customer feedback. Mac OS X Public Beta expired and ceased to function in Spring 2001.<ref>{{cite web | url=http://www.macobserver.com/tmo/article/Mac_OS_X_Public_Beta_Expires_Today/ | title=Mac OS X Public Beta Expires Today &#124; News | publisher=The Mac Observer | accessdate=March 11, 2010}}</ref>

===Mac OS X 10.0 Cheetah===
{{Main|Mac OS X 10.0}}
[[File:MacOSX10-0screenshot.png|thumb|right|Screenshot of OS X 10.0]]
On March 24, 2001, Apple released Mac OS X 10.0 (internally codenamed Cheetah).<ref>Although the version is now called Cheetah by users, rare evidences can be found to prove that it was called so internally. For instance, a Q&A was created in 2005 which mentions it.{{cite web | title=Technical Q&A | url=https://developer.apple.com/qa/qa2004/qa1378.html | publisher=[[Apple Inc.|Apple]] | accessdate=December 20, 2006 | date=October 4, 2005}}</ref>
The initial version was slow,<ref>{{Cite news|url=https://arstechnica.com/apple/2001/04/macos-x/5/|title=Mac OS X 10.0|work=Ars Technica|access-date=2017-04-17|language=en-us}}</ref> incomplete,<ref name=":0">{{Cite web|url=http://archive.arstechnica.com/reviews/01q2/macos-x-final/macos-x-17.html|title=Mac OS X 10.0 - Page 17 - (03/2001)|website=archive.arstechnica.com|access-date=2017-04-29}}</ref> and had very few applications available at the time of its launch, mostly from independent developers.<ref>{{Cite book|url=https://books.google.com/books?id=S0AnCgAAQBAJ&pg=PA280&dq=Mac+OS+X+had+few+applications+available+at+launch,+from+independent+developers&hl=en&sa=X&ved=0ahUKEwjJqo6Uqe_WAhXEzIMKHVwJCY4Q6AEIJjAA#v=onepage&q=Mac%20OS%20X%20had%20few%20applications%20available%20at%20launch,%20from%20independent%20developers&f=false|title=Getting StartED with Mac OS X Leopard|last=Williams|first=Justin|date=2008-03-11|publisher=Apress|isbn=9781430205197|language=en}}</ref> While many critics suggested that the operating system was not ready for mainstream adoption, they recognized the importance of its initial launch as a base on which to improve.<ref name=":0" /> Simply releasing Mac OS X was received by the Macintosh community as a great accomplishment,<ref name=":0" /> for attempts to completely overhaul the Mac OS had been underway since 1996, and delayed by countless setbacks. Following some bug fixes, [[kernel panic]]s became much less frequent.{{citation needed|date=March 2014}}

===Mac OS X 10.1 Puma===
{{Main|Mac OS X 10.1}}

Later that year on September 25, 2001, Mac OS X 10.1 (internally codenamed Puma) was released. It featured increased performance and provided missing features, such as DVD playback. Apple released 10.1 as a free upgrade CD for 10.0 users, in addition to the US$129 boxed version for people running [[Mac OS 9]]. It was discovered that the upgrade CDs were full install CDs that could be used with Mac OS 9 systems by removing a specific file; Apple later re-released the CDs in an actual stripped-down format that did not facilitate installation on such systems.<ref name="pumaupgrade">{{cite web | url=http://apple.slashdot.org/article.pl?sid=01/11/29/1522209 | title=Apple Cease-And-Desists Stupidity Leak | year=2001 | publisher=Slashdot | accessdate=November 5, 2008}}</ref> On January 7, 2002, Apple announced that Mac OS X was to be the default operating system for all Macintosh products by the end of that month.<ref name="default os">{{cite press release | url=https://www.apple.com/pr/library/2002/jan/07macosx.html | title=Apple Makes Mac OS X the Default Operating System on All Macs | date=January 7, 2002 | accessdate=December 3, 2006 | publisher=[[Apple Inc.|Apple]]}}</ref>

===Mac OS X 10.2 Jaguar===
{{Main|Mac OS X 10.2}}

On August 23, 2002,<ref>{{cite press release | url=https://www.apple.com/pr/library/2002/aug/23jaguar.html | title=Jaguar "Unleashed" at 10:20&nbsp;pm Tonight | date=August 23, 2002 | accessdate=December 15, 2008 | publisher=[[Apple Inc.|Apple]]}}</ref> Apple followed up with Mac OS X 10.2 Jaguar, the first release to use its code name as part of the branding.<ref>The headline of the press release mention "Jaguar", while the codename was not mentioned for earlier versions. See [https://www.apple.com/pr/library/2002/may/06jaguar.html Apple.com], "Jaguar" press release, compared to [https://www.apple.com/pr/library/2001/jan/09macosx.html Mac OS X v10.0 press release] and [https://www.apple.com/pr/library/2001/sep/25osx_available.html Mac OS X v10.1 press release]</ref>
It brought great raw performance improvements, a sleeker look, and many powerful user-interface enhancements (over 150, according to Apple<ref>{{cite web
 |title=Mac OS X 10.2 Product Information Page 
 |url=https://www.apple.com/macosx/ 
 |accessdate=June 12, 2008 
 |date=August 29, 2002 
 |publisher=[[Apple Inc.|Apple]] 
 |archiveurl=https://web.archive.org/web/20020829042532/http://www.apple.com/macosx/ 
 |archivedate=August 29, 2002 
 |deadurl=yes 
 |df= 
}}</ref>
), including [[Quartz Compositor|Quartz Extreme]] for compositing graphics directly on an [[ATI Technologies|ATI]] [[Radeon]] or [[Nvidia]] [[GeForce 2 Series|GeForce2]] MX AGP-based video card with at least 16&nbsp;MB of VRAM, a system-wide repository for contact information in the new [[Address Book (application)|Address Book]], and an instant messaging client named [[iChat]].<ref>{{cite press release | title=Apple Previews "Jaguar," the Next Major Release of Mac OS X | url=https://www.apple.com/pr/library/2002/may/06jaguar.html | accessdate=December 20, 2006 | date=May 6, 2002 | publisher=[[Apple Inc.|Apple]]}}</ref> The [[Happy Mac]] which had appeared during the Mac OS startup sequence for almost 18 years was replaced with a large grey Apple logo with the introduction of Mac OS X v10.2.<ref>{{Cite web|url=http://lowendmac.com/thomas/tt07/0823.html|title=Murder on Macintosh Row: Happy Mac, 1984-2002|last=Thomas|first=Tommy|website=lowendmac.com|language=en|access-date=2017-04-29}}</ref>

===Mac OS X 10.3 Panther===
{{Main|Mac OS X Panther}}

[[Mac OS X v10.3]] Panther was released on October 24, 2003. In addition to providing much improved performance, it also incorporated the most extensive update yet to the user interface. Panther included as many or more new features as Jaguar had the year before, including an updated Finder, incorporating a brushed-metal interface, [[Fast user switching]], [[Exposé (Mac OS X)|Exposé]] (Window manager), [[FileVault]], [[Safari (web browser)|Safari]], iChat AV (which added [[videoconferencing]] features to iChat), improved [[Portable Document Format]] (PDF) rendering and much greater [[Microsoft Windows]] interoperability.<ref>{{cite press release | url=https://www.apple.com/pr/library/2003/oct/08panther.html | title=Apple Announces Mac OS X "Panther" | date=October 8, 2003 | accessdate=January 11, 2007 | publisher=[[Apple Inc.|Apple]]}}</ref> Support for some early G3 computers such as "beige" Power Macs and "WallStreet" PowerBooks was discontinued.<ref>{{Cite news|url=http://lowendmac.com/2003/mac-os-x-10-3-panther/|title=Mac OS X 10.3 Panther|date=2003-10-24|newspaper=Low End Mac|language=en-US|access-date=2016-12-31}}</ref>

===Mac OS X 10.4 Tiger===
{{Main|Mac OS X Tiger}}
[[File:TigerDesk.png|thumb|right|Screenshot of Tiger]]

Mac OS X 10.4 Tiger was released on April 29, 2005. Apple stated that Tiger contained more than 200 new features.<ref>{{cite press release | title=Apple Unleashes "Tiger Friday at 6:00&nbsp;pm | url=https://www.apple.com/pr/library/2005/apr/28tiger.html | date=April 28, 2005 | accessdate=January 11, 2007 | publisher=[[Apple Inc.|Apple]]}}</ref> As with Panther, certain older machines were no longer supported; Tiger requires a Mac with 256&nbsp;MB and a built-in [[FireWire]] port.<ref name="TigerRequirements" /> Among the new features, Tiger introduced [[Spotlight (software)|Spotlight]], [[Dashboard (Mac OS)|Dashboard]], [[Virtual folder|Smart Folders]], updated Mail program with Smart Mailboxes, [[QuickTime]] 7, [[Safari (web browser)|Safari]] 2, [[Automator (software)|Automator]], [[VoiceOver]], [[Core Image]] and [[Core Video]]. The initial release of the [[Apple TV]] used a modified version of Tiger with a different graphical interface and fewer applications and services. On January 10, 2006, Apple released the first Intel-based Macs along with the 10.4.4 update to Tiger. This operating system functioned identically on the PowerPC-based Macs and the new Intel-based machines, with the exception of the Intel release dropping support for the Classic environment.<ref>{{cite web | url=http://www.appleinsider.com/articles/06/01/10/apple_unveils_intel_imacs.html | title=Apple unveils Intel iMacs | publisher=AppleInsider | date=January 2006 | accessdate=December 15, 2008}}</ref>

===Mac OS X 10.5 Leopard===
{{Main|Mac OS X Leopard}}

Mac OS X 10.5 Leopard was released on October 26, 2007. It was called by Apple "the largest update of Mac OS X". It brought more than 300 new features.<ref>{{cite web | url=https://www.apple.com/macosx/features/300.html | title=Apple&nbsp;– Mac OS X Leopard&nbsp;– Features&nbsp;– 300+ New Features | year=2008 | accessdate=June 13, 2008 | publisher=[[Apple Inc.|Apple]] | archiveurl=https://web.archive.org/web/20080501175556/http://www.apple.com/macosx/features/300.html | archivedate=May 1, 2008}}</ref> Leopard supports both [[PowerPC]]- and [[X86|Intel x86]]-based Macintosh computers; support for the G3 processor was dropped and the G4 processor required a minimum clock rate of 867&nbsp;MHz, and at least 512&nbsp;MB of [[Random-access memory|RAM]] to be installed. The single DVD works for all supported Macs (including 64-bit machines). New features include a new look, an updated Finder, [[Time Machine (Apple software)|Time Machine]], [[Spaces (software)|Spaces]], [[Boot Camp (software)|Boot Camp]] pre-installed,<ref name="bootcamp">{{cite web | url=https://www.apple.com/macosx/bootcamp/ | title=Apple&nbsp;– BootCamp | year=2006 | accessdate=June 5, 2006 | publisher=[[Apple Inc.|Apple]] |archiveurl = https://web.archive.org/web/20060602044022/http://www.apple.com/macosx/bootcamp/ |archivedate = June 2, 2006}}</ref> full support for [[64-bit]] applications (including graphical applications), new features in [[Mail (OS X)|Mail]] and [[iChat]], and a number of new security features. Leopard is an [[Single UNIX Specification|Open Brand UNIX 03]] registered product on the Intel platform. It was also the first [[Berkeley Software Distribution|BSD-based]] OS to receive UNIX 03 certification.<ref name=leopard_unix_cert /><ref>{{cite web | publisher=[[Apple Inc.|Apple]] | title=Mac OS X Leopard&nbsp;– Technology&nbsp;– UNIX | url=https://www.apple.com/server/macosx/technology/unix.html | work=Leopard Technology Overview | accessdate=October 26, 2007 | quote=Leopard is now an Open Brand UNIX 03 Registered Product, conforming to the SUSv3 and POSIX 1003.1 specifications for the C API, Shell Utilities, and Threads.}}</ref> Leopard dropped support for the [[Classic Environment]] and all Classic applications.<ref>{{cite web | url=http://docs.info.apple.com/article.html?artnum=303137 | title=Do Classic applications work with Mac OS X 10.5 or Intel-based Macs? | publisher=[[Apple Inc.|Apple]] | work=Knowledge Base | date=January 13, 2006 | accessdate=October 25, 2007}}</ref> It was the final version of Mac OS X to support the PowerPC architecture.<ref>{{Cite book|url=https://books.google.com/books?id=B2iloXnZZNAC&pg=PT34&dq=mac+os+x+leopard+10.5+last+version+to+support+power+pc&hl=en&sa=X&ved=0ahUKEwi3wMfh2PnTAhUJ0mMKHewvAFcQ6AEIIjAB|title=Cocoa Recipes for Mac OS X|last=Cheeseman|first=Bill|date=2010-04-26|publisher=Pearson Education|isbn=9780321702883|language=en}}</ref>

===Mac OS X 10.6 Snow Leopard===
{{Main|Mac OS X Snow Leopard}}

Mac OS X 10.6 Snow Leopard was released on August 28, 2009. Rather than delivering big changes to the appearance and end user functionality like the previous releases of {{nowrap|Mac OS X}}, Snow Leopard focused on "under the hood" changes, increasing the performance, efficiency, and stability of the operating system. For most users, the most noticeable changes were: the disk space that the operating system frees up after a clean install compared to Mac OS X 10.5 Leopard, a more responsive [[Finder (software)|Finder]] rewritten in [[Cocoa (API)|Cocoa]], faster [[Time Machine (Apple software)|Time Machine]] backups, more reliable and user friendly disk ejects, a more powerful version of the Preview application, as well as a faster [[Safari (web browser)|Safari]] web browser.  Snow Leopard only supported machines with Intel CPUs, required at least 1&nbsp;GB of [[Random-access memory|RAM]], and dropped default support for applications built for the [[PowerPC]] architecture ([[Rosetta (software)|Rosetta]] could be installed as an additional component to retain support for PowerPC-only applications).<ref>{{cite web | first=Steven | last=Lynch | url=http://www.hardocp.com/news/2008/06/11/snow_leopard_will_support_powerpcs | publisher=HardOCP | title=Mac OS X Snow Leopard Drops PowerPC Support | date=June 12, 2008 | accessdate=October 20, 2010}}</ref>

Snow Leopard also featured new [[64-bit computing|64-bit]] technology capable of supporting greater amounts of [[Random-access memory|RAM]], improved support for multi-core processors through [[Grand Central Dispatch]], and advanced GPU performance with [[OpenCL]].<ref>{{Cite news|url=http://lowendmac.com/2009/the-64-bitness-of-mac-os-x-10-6-snow-leopard/|title=The 64-Bitness of Mac OS X 10.6 Snow Leopard|date=2009-08-19|newspaper=Low End Mac|language=en-US|access-date=2016-12-31}}</ref>

An update introduced support for the [[Mac App Store]], Apple's digital distribution platform for macOS applications.<ref>{{cite web|url=http://news.cnet.com/8301-13506_3-20027548-17.html |title=Mac App Store launches on Snow Leopard |first=Don |last=Reisinger|date=January 6, 2011|publisher=[[CBS Interactive]]|work=CNET}}</ref>

[[File:WWDC 2011 Moscone West Interior.jpg|thumb|250px|Mac OS X Lion was announced at [[WWDC]] 2011 at [[Moscone West]] ]]

===Mac OS X 10.7 Lion===
{{Main|Mac OS X Lion}}

Mac OS X 10.7 Lion was released on July 20, 2011. It brought developments made in Apple's iOS, such as an easily navigable display of installed applications called [[Launchpad (Mac OS X)|Launchpad]] and a greater use of [[multi-touch]] gestures, to the Mac. This release removed [[Rosetta (software)|Rosetta]], making it incompatible with PowerPC applications.<ref name="MacRumors: Mac OS X Lion: Drops PowerPC Emulation, Adds QuickTime Pro Features, Much More" />

Changes made to the GUI include auto-hiding scrollbars that only appear when they are being used, and Mission Control which unifies Exposé, Spaces, Dashboard, and full-screen applications within a single interface.<ref>{{cite web | title=Apple – OS X Lion – The world's most advanced desktop operating system. | url=https://www.apple.com/macosx/lion/ | date=October 20, 2010 | accessdate=October 20, 2010 | publisher=[[Apple Inc.|Apple]]}}</ref> Apple also made changes to applications: they resume in the same state as they were before they were closed, similar to iOS. Documents auto-save by default.<ref>{{cite web | title=Mac OS X 10.7 Lion Review - Document Model | url=https://arstechnica.com/apple/2011/07/mac-os-x-10-7/7/#document-model | date=July 20, 2011 | accessdate=December 11, 2016 | publisher=[[Ars Technica]]}}</ref>

===OS X 10.8 Mountain Lion===
{{Main|OS X Mountain Lion}}

OS X 10.8 Mountain Lion was released on July 25, 2012.<ref name="PR-25-07" /> Following the release of Lion the previous year, it was the first of the annual rather than two-yearly updates to OS X (and later macOS), which also closely alined with the annual iOS operating system updates. It incorporates some features seen in iOS 5, which include [[Game Center]], support for [[iMessage]] in the new [[Messages (Apple)|Messages]] messaging application, and Reminders as a to-do list app separate from [[iCal]] (which is renamed as Calendar, like the iOS app). It also includes support for storing [[iWork]] documents in [[iCloud]].<ref>{{cite web| title=Apple – OS X Mountain Lion – The world's most advanced desktop operating system.| url=https://www.apple.com/macosx/mountain-lion/| date=February 16, 2012| accessdate=February 16, 2012| publisher=[[Apple Inc.|Apple]]}}</ref> [[Notification Center]], which makes its debut in Mountain Lion, is a desktop version similar to the one in iOS 5.0 and higher. Application pop-ups are now concentrated on the corner of the screen, and the Center itself is pulled from the right side of the screen. Mountain Lion also includes more Chinese features including support for [[Baidu]] as an option for [[Safari (web browser)|Safari]] search engine, [[Tencent QQ|QQ]], [[163.com]] and 126.com services for [[Mail (OS X)|Mail]], [[Address Book (application)|Contacts]]  and [[iCal|Calendar]], [[Youku]], [[Tudou]] and [[Sina Weibo]] are integrated into share sheets.<ref name="chinamtnlion" />

Starting with Mountain Lion, Apple software updates (including the OS) are distributed via the [[Mac App Store|App Store]].<ref>{{Cite web|url=http://appleinsider.com/articles/12/02/22/inside_os_x_108_mountain_lion_apple_overhauls_software_updates_app_store|title=Inside OS X 10.8 Mountain Lion: Apple overhauls software updates, App Store|website=AppleInsider|language=en-US|access-date=2017-04-29}}</ref> This updating mechanism replaced the Apple Software Update utility.<ref>{{Cite web|url=https://www.macrumors.com/2012/02/16/software-update-to-move-inside-mac-app-store-in-os-x-mountain-lion/|title=Software Update to Move Inside Mac App Store in OS X Mountain Lion|last=Slivka|first=Eric|access-date=2017-04-29}}</ref>
[[File:Macintosh OS X Mavericks representation.png|thumb|right|A screenshot of OS X Mavericks]]

===OS X 10.9 Mavericks===
{{Main|OS X Mavericks}}

OS X 10.9 Mavericks was released on October 22, 2013. It was a free upgrade to all users running Snow Leopard or later with a 64-bit Intel processor.<ref>{{cite web |date= Oct 22, 2013 |first1=  Poornima |last1= Gupta |first2= Edwin |last2= Chan  |url= https://www.reuters.com/article/us-apple-ipad-idUSBRE99L0ZK20131022 |title= Apple gives away Mac software, unveils iPad Air |publisher= Reuters }}</ref> Its changes include the addition of the previously iOS-only [[Apple Maps|Maps]] and [[iBooks]] applications, improvements to the Notification Center, enhancements to several applications, and many under-the-hood improvements.<ref>{{cite press release|url=https://www.apple.com/pr/library/2013/10/23OS-X-Mavericks-Available-Today-Free-from-the-Mac-App-Store.html|title=OS X Mavericks Available Today Free from the Mac App Store|date=October 22, 2013|publisher=[[Apple Inc.]]}}</ref>

===OS X 10.10 Yosemite===
{{Main|OS X Yosemite}}

OS X 10.10 Yosemite was released on October 16, 2014. It features a redesigned user interface similar to that of [[iOS 7]], intended to feature a more minimal, text-based 'flat' design, with use of translucency effects and intensely [[Colorfulness|saturated colors]].<ref name="Yosemite review Siracusa">{{cite web|last1=Siracusa|first1=John|title=Yosemite review|url=https://arstechnica.com/apple/2014/10/os-x-10-10/3/|website=Ars Technica}}</ref> Apple's showcase new feature in Yosemite is Handoff, which enables users with iPhones running iOS 8.1 or later to answer phone calls, receive and send SMS messages, and complete unfinished iPhone emails on their Mac. As of OS X 10.10.3, [[Photos (Apple)|Photos]] replaced [[iPhoto]] and [[Aperture (software)|Aperture]].<ref>{{cite news | url = https://www.theguardian.com/technology/2015/apr/16/upgrading-from-iphoto-aperture-apples-photos-read-this | date = 16 April 2015 | accessdate = 27 July 2017 | first = Samuel | last = Gibbs | newspaper = [[The Guardian]] | location = London | title = Upgrading from iPhoto or Aperture to Apple's Photos? Read this}}</ref>

===OS X 10.11 El Capitan===
{{Main|OS X El Capitan}}
[[File:El capitan desktop display.png|thumb|Screenshot of El Capitan]]
OS X 10.11 El Capitan was released on September 30, 2015. Similar to Mac OS X 10.6 Snow Leopard, Apple described this release as containing "refinements to the Mac experience" and "improvements to system performance" rather than new features. Refinements include public transport built into the [[Apple Maps|Maps]] application, GUI improvements to the [[Notes (Apple)|Notes]] application, adopting [[San Francisco (2014 typeface)|San Francisco]] as the system font for clearer legibility, and the introduction of [[System Integrity Protection]]. The [[Metal (API)|Metal API]], first introduced in [[iOS 8]], was also included in this operating system for "all Macs since 2012".<ref>{{cite web|url = http://devstreaming.apple.com/videos/wwdc/2015/6037pi9rxl6tfss8w/603/603_whats_new_in_metal_part_1.pdf|title = What’s New in Metal, Part 1|date = June 2015|accessdate = June 17, 2015|website = [[Apple Developer]]|publisher = Apple|last = Dhiraj|first = Rav|page = 84|format = pdf}}</ref>

===macOS 10.12 Sierra===
{{Main|macOS Sierra}}
macOS 10.12 Sierra was released to the public on September 20, 2016. New features include the addition of [[Siri]], Optimized Storage, and updates to Photos, Messages, and iTunes.<ref name="macossierraweb">{{cite web|url=https://www.apple.com/macos/sierra/|title=macOS|accessdate=September 26, 2016}}</ref><ref name="siri3">{{cite web | url=http://appleinsider.com/articles/16/06/14/siri-for-mac-how-it-works-in-apples-macos-sierra-and-what-its-capable-of | accessdate=September 28, 2016 | title=Siri for Mac: How it works in Apple's macOS Sierra and what it's capable of | publisher=[[AppleInsider]]}}</ref>

===macOS 10.13 High Sierra===
{{Main|macOS High Sierra}}
The fall release of macOS 10.13 High Sierra was announced on June 5, 2017 at Apple's [[Apple Worldwide Developers Conference|WWDC]] event.<ref name=":1">{{Cite news|url=http://osxdaily.com/2017/06/05/macos-10-13-high-sierra-release-fall/|title=MacOS 10.13 High Sierra Release Date Set for Fall|date=2017-06-05|work=OS X Daily|access-date=2017-10-12|language=en-US}}</ref> On September 12, 2017 at Apple's [[iPhone]] event, they announced its release to be September 25, 2017.<ref>{{Cite news|url=https://techcrunch.com/2017/09/12/macos-high-sierra-release-date/|title=Apple is releasing macOS High Sierra on September 25|last=Dillet|first=Romain|work=TechCrunch|access-date=2017-10-12|language=en}}</ref> Like [[OS X El Capitan]] and [[OS X Mountain Lion]], High Sierra is a refinement-based update having very few new features.<ref>{{Cite news|url=https://www.theverge.com/2017/6/29/15886832/apple-macos-high-sierra-preview-features|title=Apple macOS High Sierra preview: the biggest Mac update you’ll never see|work=The Verge|access-date=2017-10-13}}</ref> High Sierra uses the new [[Apple File System]] and includes enhancements to Safari, Photos, and Mail, among other changes.<ref name=":1" />

==Reception==

===Usage share===
{{See also|Usage share of operating systems}}

As of July 2016, macOS is the second-most-active general-purpose desktop client operating system in use on the [[World Wide Web]] following [[Microsoft Windows]], with a 4.90% usage share according to statistics compiled by the [[Wikimedia Foundation]]. It is the second most widely-used desktop operating system (for web browsing), after Windows, and is estimated at approximately five times the usage of [[Linux]] (which has 1.01%). Usage share generally continues to shift away from the desktop and toward mobile operating systems such as [[iOS]] and [[Android (operating system)|Android]].<ref name="wikimediastats">{{Cite web| url = https://analytics.wikimedia.org/dashboards/browsers/#all-sites-by-os/os-family-and-major-hierarchical-view | title = Wikimedia Traffic Analysis Report - Operating Systems, Jun27-Jul31, 2016}}</ref>

===Malware and spyware===
In its earlier years, Mac OS X enjoyed a near-absence of the types of [[malware]] and [[spyware]] that have affected [[Microsoft Windows]] users.<ref>{{cite web|url=http://www.informationweek.com/news/showArticle.jhtml?articleID=196800670&pgno=4 |first=John|last=Welch|title=Review: Mac OS X Shines In Comparison With Windows Vista|publisher=Information Week|date=January 6, 2007|accessdate=February 5, 2007}}</ref><ref>{{cite web|url=https://www.theregister.co.uk/2003/10/06/linux_vs_windows_viruses/|first=Scott|last=Granneman|title=Linux vs. Windows Viruses|publisher=The Register|date=October 6, 2003|accessdate=February 5, 2007 }}</ref><ref>{{cite web|last=Gruber|first=John|authorlink=John Gruber|date=June 4, 2004|url=http://daringfireball.net/2004/06/broken_windows|title=Broken Windows|publisher=[[Daring Fireball]]|accessdate=April 24, 2006}}</ref> macOS has a smaller usage share compared to Windows,<ref>{{cite web|url=http://marketshare.hitslink.com/operating-system-market-share.aspx?qprid=8|title=Operating System Market Share|accessdate=April 10, 2009|date=September 2009}}</ref> but it also has traditionally more secure [[Unix]] roots. [[Computer worm|Worms]], as well as potential vulnerabilities, were noted in 2006, which led some industry analysts and anti-virus companies to issue warnings that Apple's Mac OS X is not immune to malware.<ref>{{cite web|url=http://www.eweek.com/article2/0,1895,1929342,00.asp|title=New Safari Flaw, Worms Turn Spotlight on Apple Security|publisher=[[eWeek]]|author=Roberts, Paul|date=February 21, 2006|accessdate=November 23, 2007}}</ref> Increasing market share coincided with additional reports of a variety of attacks.<ref>{{cite web|url=http://www.betanews.com/article/Macs-dont-get-viruses-myth-dissolves-before-publics-eyes/1251493625 |title='Macs don't get viruses' myth dissolves before public's eyes|first= Tim |last=Conneally |date=August 28, 2009 |publisher=BetaNews.com}}</ref> In early 2011, Mac OS X experienced a large increase in malware attacks,<ref>{{cite web|last=Grimes |first=Roger A. |url=http://www.infoworld.com/d/security/7-questions-about-the-mac-malware-scare-811 |title=7 questions about the Mac malware scare &#124; Security |publisher=InfoWorld |date=May 23, 2011 |accessdate=July 5, 2011}}</ref> and malware such as [[Mac Defender]], MacProtector, and MacGuard were seen as an increasing problem for Mac users. At first, the malware installer required the user to enter the administrative password, but later versions were able to install without user input.<ref>{{cite web|url=http://www.ibtimes.com/articles/152612/20110526/mac-security-boasts-threatened-by-malware-surge.htm |title=Mac Security Boasts Threatened by Malware Surge – International Business Times |publisher=Ibtimes.com |date=May 26, 2011 |accessdate=July 5, 2011}}</ref> Initially, Apple support staff were instructed not to assist in the removal of the malware or admit the existence of the malware issue, but as the malware spread, a support document was issued. Apple announced an OS X update to fix the problem. An estimated 100,000 users were affected.<ref>{{cite web|last=Trenholm |first=Rich |url=http://crave.cnet.co.uk/software/apple-tells-support-staff-not-to-confirm-mac-defender-infections-50003832/ |title=Apple tells support staff not to confirm Mac Defender infections|publisher=Crave. |location=UK|date=May 20, 2011 |accessdate=July 5, 2011}}</ref><ref>{{cite news|url=http://blogs.pcmag.com/securitywatch/2011/05/mac_defender_20_released.php |title=Mac Defender 2.0 Released – Security Watch |work=PC Mag |date=May 25, 2011 |accessdate=July 5, 2011 |first=Larry |last=Seltzer}}</ref> Apple releases security updates for macOS regularly.<ref>{{cite web|title=Apple security updates|publisher=Apple|date=January 21, 2009|url=http://support.apple.com/kb/HT1222|accessdate=January 29, 2009}}</ref>

===Promotion===
As a devices company, most large-scale Apple promotion for macOS has been part of the sale of Macs, with promotion of macOS updates generally focused on existing users, promotion at [[Apple Store]] and other retail partners, or through events for developers. In larger scale advertising campaigns, Apple specifically promoted macOS as better for handling media and other home-user applications, and [[Get a Mac#North American campaign|comparing]] Mac OS X (especially versions Tiger and Leopard) with the heavy criticism [[Microsoft]] received for the long-awaited [[Windows Vista]] operating system.<ref name="Apple's Get a Mac campaign">{{cite web|last1=Nudd|first1=Tim|title=Apple's Get a Mac campaign|url=http://www.adweek.com/adfreak/apples-get-mac-complete-campaign-130552|website=AdWeek|accessdate=2 December 2015}}</ref><ref name="Apple tweaks Microsoft over Vista ad spending">{{cite web|last1=Arthur|first1=Charles|title=Apple tweaks Microsoft over Vista ad spending|url=https://www.theguardian.com/technology/blog/2008/oct/23/apple-microsoft-vista-advertising|website=[[The Guardian]]|accessdate=2 December 2015}}</ref>

==See also==
{{portal|Apple}}{{Div col}}
* [[Macintosh operating systems]]
* [[Classic Mac OS]] (1984–2001)
* [[Comparison of BSD operating systems]]
* [[Comparison of operating systems]]
* [[List of operating systems]]
* [[List of Macintosh software]]
* [[List of macOS technologies]]
* [[Dock (macOS)]]
{{Div col end}}

==References==
{{Reflist|30em}}

==External links==
**{{Official website|https://www.apple.com/macos|macOS}} – official site

{{macOS}}
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{{Mac OS History}}
{{Apple Inc. operating systems}}
{{Apple software}}
{{Apple}}
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[[Category:Apple Inc. operating systems]]
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