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Available in 21 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-21" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">21 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%A5%D9%83%D8%B3_%D8%A3%D9%86_%D9%8A%D9%88" title="إكس أن يو – Arabic" lang="ar" hreflang="ar" data-title="إكس أن يو" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/XNU" title="XNU – Catalan" lang="ca" hreflang="ca" data-title="XNU" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/XNU" title="XNU – Czech" lang="cs" hreflang="cs" data-title="XNU" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/XNU" title="XNU – German" lang="de" hreflang="de" data-title="XNU" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/XNU" title="XNU – Spanish" lang="es" hreflang="es" data-title="XNU" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A7%DB%8C%DA%A9%D8%B3%E2%80%8C%D8%A7%D9%86%E2%80%8C%DB%8C%D9%88" title="ایکس‌ان‌یو – Persian" lang="fa" hreflang="fa" data-title="ایکس‌ان‌یو" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/XNU" title="XNU – French" lang="fr" hreflang="fr" data-title="XNU" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/XNU" title="XNU – Korean" lang="ko" hreflang="ko" data-title="XNU" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/XNU" title="XNU – Italian" lang="it" hreflang="it" data-title="XNU" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/XNU" title="XNU – Hebrew" lang="he" hreflang="he" data-title="XNU" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/XNU" title="XNU – Dutch" lang="nl" hreflang="nl" data-title="XNU" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/XNU" title="XNU – Japanese" lang="ja" hreflang="ja" data-title="XNU" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/XNU" title="XNU – Polish" lang="pl" hreflang="pl" data-title="XNU" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/XNU" title="XNU – Portuguese" lang="pt" hreflang="pt" data-title="XNU" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/XNU" title="XNU – Russian" lang="ru" hreflang="ru" data-title="XNU" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/XNU" title="XNU – Finnish" lang="fi" hreflang="fi" data-title="XNU" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/XNU" title="XNU – Swedish" lang="sv" hreflang="sv" data-title="XNU" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/XNU" title="XNU – Turkish" lang="tr" hreflang="tr" data-title="XNU" data-language-autonym="Türkçe" data-language-local-name="Turkish" 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print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="/wiki/GNU" title="GNU">GNU</a>.</div><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Operating system</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vevent"><caption class="infobox-title summary">XNU</caption><tbody><tr><td colspan="2" class="infobox-image"><span typeof="mw:File"><a href="/wiki/File:The_XNU_Kernel_Graphic.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/26/The_XNU_Kernel_Graphic.svg/330px-The_XNU_Kernel_Graphic.svg.png" decoding="async" width="300" height="183" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/26/The_XNU_Kernel_Graphic.svg/500px-The_XNU_Kernel_Graphic.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/26/The_XNU_Kernel_Graphic.svg/600px-The_XNU_Kernel_Graphic.svg.png 2x" data-file-width="512" data-file-height="313" /></a></span><div class="infobox-caption">The XNU kernel</div></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programmer" title="Programmer">Developer</a></th><td class="infobox-data"><a href="/wiki/Apple_Inc." title="Apple Inc.">Apple Inc.</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programming_language" title="Programming language">Written in</a></th><td class="infobox-data"><a href="/wiki/C_(programming_language)" title="C (programming language)">C</a>, <a href="/wiki/C%2B%2B" title="C++">C++</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">OS family</th><td class="infobox-data"><a href="/wiki/Unix-like" title="Unix-like">Unix-like</a> (before 2007), <a href="/wiki/Unix" title="Unix">Unix</a><sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Working state</th><td class="infobox-data">Current</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Source model</th><td class="infobox-data"><a href="/wiki/Open-source_software" title="Open-source software">Open-source</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">December 1996<span class="noprint">; 28 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">1996-12</span>)</span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Repository_(version_control)" title="Repository (version control)">Repository</a></th><td class="infobox-data"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style><div class="plainlist"><ul><li><span class="url"><a rel="nofollow" class="external text" href="https://github.com/apple-oss-distributions/xnu">github<wbr />.com<wbr />/apple-oss-distributions<wbr />/xnu</a></span> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q14583#P1324" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></li></ul> </div></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Platforms</th><td class="infobox-data">Current: <a href="/wiki/X86-64" title="X86-64">x86-64</a>, <a href="/wiki/AArch64" title="AArch64">64-bit ARM</a>, <a href="/wiki/ARM_architecture#32-bit_architecture" class="mw-redirect" title="ARM architecture">32-bit ARM</a> (32-bit ARM support is closed-source)<br />Historical: <a href="/wiki/PowerPC" title="PowerPC">PowerPC</a> (32-bit and 64-bit), <a href="/wiki/IA-32" title="IA-32">IA-32</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Kernel_(operating_system)" title="Kernel (operating system)">Kernel</a> type</th><td class="infobox-data"><a href="/wiki/Hybrid_kernel" title="Hybrid kernel">Hybrid</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_license" title="Software license">License</a></th><td class="infobox-data"><a href="/wiki/Apple_Public_Source_License" title="Apple Public Source License">Apple Public Source License</a> 2.0</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Preceded by</th><td class="infobox-data"><a href="/wiki/Mach_(kernel)" title="Mach (kernel)">Mach</a>, <a href="/wiki/Nukernel" title="Nukernel">Nukernel</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Official website</th><td class="infobox-data"><span class="url"><a rel="nofollow" class="external text" href="https://github.com/apple-oss-distributions/xnu">github<wbr />.com<wbr />/apple-oss-distributions<wbr />/xnu</a></span></td></tr></tbody></table> <p><b>XNU</b> ("X is Not Unix") is the computer <a href="/wiki/Operating_system" title="Operating system">operating system</a> (OS) <a href="/wiki/Kernel_(operating_system)" title="Kernel (operating system)">kernel</a> developed at <a href="/wiki/Apple_Inc." title="Apple Inc.">Apple Inc.</a> since December 1996 for use in the Mac OS X (now <a href="/wiki/MacOS" title="MacOS">macOS</a>) operating system and released as <a href="/wiki/Free_and_open-source_software" title="Free and open-source software">free and open-source software</a> as part of the <a href="/wiki/Darwin_(operating_system)" title="Darwin (operating system)">Darwin</a> OS, which, in addition to being the basis for macOS, is also the basis for <a href="/wiki/Apple_TV_Software" class="mw-redirect" title="Apple TV Software">Apple TV Software</a>, <a href="/wiki/IOS" title="IOS">iOS</a>, <a href="/wiki/IPadOS" title="IPadOS">iPadOS</a>, <a href="/wiki/WatchOS" title="WatchOS">watchOS</a>, <a href="/wiki/VisionOS" title="VisionOS">visionOS</a>, and <a href="/wiki/TvOS" title="TvOS">tvOS</a>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>XNU was originally developed by <a href="/wiki/NeXT" title="NeXT">NeXT</a> for the <a href="/wiki/NeXTSTEP" title="NeXTSTEP">NeXTSTEP</a> operating system. It was a <a href="/wiki/Hybrid_kernel" title="Hybrid kernel">hybrid kernel</a> derived from version 2.5 of the <a href="/wiki/Mach_(kernel)" title="Mach (kernel)">Mach kernel</a> developed at <a href="/wiki/Carnegie_Mellon_University" title="Carnegie Mellon University">Carnegie Mellon University</a>, which incorporated the bulk of the <a href="/wiki/History_of_the_Berkeley_Software_Distribution#4.3BSD" title="History of the Berkeley Software Distribution">4.3BSD</a> kernel modified to run atop Mach primitives, along with an <a href="/wiki/Application_programming_interface" class="mw-redirect" title="Application programming interface">application programming interface</a> (API) in <a href="/wiki/Objective-C" title="Objective-C">Objective-C</a> for writing drivers named DriverKit.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>After Apple acquired NeXT, the kernel was updated with code derived from <a href="/wiki/OSFMK" class="mw-redirect" title="OSFMK">OSFMK</a> 7.3 from <a href="/wiki/Open_Software_Foundation" title="Open Software Foundation">OSF</a>,<sup id="cite_ref-wwdc-2000-session-106_4-0" class="reference"><a href="#cite_note-wwdc-2000-session-106-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> and the <a href="/wiki/FreeBSD" title="FreeBSD">FreeBSD</a> project, and the DriverKit was replaced with new API on a restricted subset of <a href="/wiki/C%2B%2B" title="C++">C++</a><sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> (based on <a href="/wiki/Embedded_C%2B%2B" title="Embedded C++">Embedded C++</a>)<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> named IOKit. </p><p>By keeping the BSD kernel into the third part of XNU,<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> XNU became UNIX-based when macOS achieved UNIX certification under the Single UNIX Specification (SUS) by The Open Group.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> Despite this, Apple retained the original 'XNU' name, which stands for 'X is Not Unix,' a relic from its NeXTSTEP origins before macOS was UNIX-certified. This has led to confusion, as the name suggests that XNU is separate from UNIX, even though macOS, as a whole, is officially recognized as a UNIX operating system.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Kernel_design">Kernel design</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=1" title="Edit section: Kernel design"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>XNU is a <a href="/wiki/Hybrid_kernel" title="Hybrid kernel">hybrid kernel</a>, containing features of both <a href="/wiki/Monolithic_kernel" title="Monolithic kernel">monolithic kernels</a> and <a href="/wiki/Microkernel" title="Microkernel">microkernels</a>, attempting to make the best use of both technologies, such as the <a href="/wiki/Message_passing" title="Message passing">message passing</a> ability of microkernels enabling greater modularity and larger portions of the OS to benefit from <a href="/wiki/Memory_protection" title="Memory protection">memory protection</a>, and retaining the speed of monolithic kernels for some critical tasks. </p><p>As of 2021<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=XNU&action=edit">[update]</a></sup>, XNU runs on <a href="/wiki/ARM64" class="mw-redirect" title="ARM64">ARM64</a> and <a href="/wiki/X86-64" title="X86-64">x86-64</a> processors, both one processor and <a href="/wiki/Symmetric_multiprocessing" title="Symmetric multiprocessing">symmetric multiprocessing</a> (SMP) models. <a href="/wiki/PowerPC" title="PowerPC">PowerPC</a> support was removed as of the version in <a href="/wiki/Mac_OS_X_Snow_Leopard" title="Mac OS X Snow Leopard">Mac OS X Snow Leopard</a>. Support for <a href="/wiki/IA-32" title="IA-32">IA-32</a> was removed as of the version in <a href="/wiki/Mac_OS_X_Lion" class="mw-redirect" title="Mac OS X Lion">Mac OS X Lion</a>; support for 32-bit ARM was removed as of the version in <span class="nowrap"><a href="/wiki/IOS_11" title="IOS 11">iOS 11</a></span>. </p> <div class="mw-heading mw-heading3"><h3 id="Mach">Mach</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=2" title="Edit section: Mach"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Mach_(kernel)" title="Mach (kernel)">Mach (kernel)</a></div> <p>The basis of the XNU kernel is a heavily modified (hybrid) <a href="/wiki/Open_Software_Foundation" title="Open Software Foundation">Open Software Foundation</a> Mach kernel (<a href="/wiki/OSFMK" class="mw-redirect" title="OSFMK">OSFMK</a>) 7.3.<sup id="cite_ref-wwdc-2000-session-106_4-1" class="reference"><a href="#cite_note-wwdc-2000-session-106-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> OSFMK 7.3 is a microkernel<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> that includes applicable code from the <a href="/wiki/University_of_Utah" title="University of Utah">University of Utah</a> Mach 4 kernel and from the many Mach 3.0 variants <a href="/wiki/Fork_(software_development)" title="Fork (software development)">forked</a> from the original <a href="/wiki/Carnegie_Mellon_University" title="Carnegie Mellon University">Carnegie Mellon University</a> Mach 3.0 microkernel. </p><p>OSFMK 7.3 is able to run the core of an operating system as separated processes, which allows a great flexibility (it could run several operating systems in parallel above the Mach core), but this often reduces performance<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (September 2024)">citation needed</span></a></i>]</sup> because of time-consuming kernel/user mode context switches and overhead stemming from mapping or copying messages between the address spaces of the kernel and that of the service daemons. </p><p>Apple licensed OSFMK 7.3 from the OSF, and attempted to streamline some tasks by building <a href="/wiki/BSD" class="mw-redirect" title="BSD">BSD</a> functions into the kernel along with the Mach code. The result is a heavily modified (hybrid) OSFMK 7.3 kernel. </p> <div class="mw-heading mw-heading3"><h3 id="BSD">BSD</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=3" title="Edit section: BSD"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Berkeley_Software_Distribution" title="Berkeley Software Distribution">Berkeley Software Distribution</a> (BSD) part of the kernel provides the Portable Operating System Interface (<a href="/wiki/POSIX" title="POSIX">POSIX</a>) <a href="/wiki/Application_programming_interface" class="mw-redirect" title="Application programming interface">application programming interface</a> (API, BSD system calls), the <a href="/wiki/Unix" title="Unix">Unix</a> process model atop Mach tasks, basic security policies, user and group ids, permissions, the network <a href="/wiki/Protocol_stack" title="Protocol stack">protocol stack</a> (protocols), the <a href="/wiki/Virtual_file_system" title="Virtual file system">virtual file system</a> code (including a <a href="/wiki/File_system" title="File system">file system</a> independent <a href="/wiki/Journaling_file_system" title="Journaling file system">journaling</a> layer), several local file systems such as <a href="/wiki/Hierarchical_File_System_(Apple)" title="Hierarchical File System (Apple)">Hierarchical File System</a> (HFS, <a href="/wiki/HFS_Plus" title="HFS Plus">HFS Plus</a> (HFS+)) and <a href="/wiki/Apple_File_System" title="Apple File System">Apple File System</a> (APFS), the <a href="/wiki/Network_File_System" title="Network File System">Network File System</a> (NFS) client and server, cryptographic framework, <a href="/wiki/UNIX_System_V" title="UNIX System V">UNIX System V</a> <a href="/wiki/Inter-process_communication" title="Inter-process communication">inter-process communication</a> (IPC), audit subsystem, <a href="/wiki/Mandatory_access_control" title="Mandatory access control">mandatory access control</a>, and some of the locking primitives.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> The BSD code present in XNU has been most recently synchronised with that from the <a href="/wiki/FreeBSD" title="FreeBSD">FreeBSD</a> kernel. Although much of it has been significantly modified, code sharing still occurs between Apple and the FreeBSD Project as of 2009<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=XNU&action=edit">[update]</a></sup>.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="K32/K64"><span id="K32.2FK64"></span>K32/K64</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=4" title="Edit section: K32/K64"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>XNU in <a href="/wiki/Mac_OS_X_Snow_Leopard" title="Mac OS X Snow Leopard">Mac OS X Snow Leopard</a>, v10.6, (<a href="/wiki/Darwin_(operating_system)" title="Darwin (operating system)">Darwin</a> version 10) comes in two varieties, a <a href="/wiki/32-bit" class="mw-redirect" title="32-bit">32-bit</a> version called <i>K32</i> and a <a href="/wiki/64-bit_computing" title="64-bit computing">64-bit</a> version called <i>K64</i>.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> K32 can run 64-bit applications in <a href="/wiki/Userland_(computing)" class="mw-redirect" title="Userland (computing)">userland</a>.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> What was new in Mac OS X 10.6 was the ability to run XNU in 64-bit <a href="/wiki/Kernel_space" class="mw-redirect" title="Kernel space">kernel space</a>. K32 was the default kernel for 10.6 <i>Server</i> when used on all machines except <a href="/wiki/Mac_Pro" title="Mac Pro">Mac Pro</a> and <a href="/wiki/Xserve" title="Xserve">Xserve</a> models from 2008 onwards<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> and can run 64-bit applications. K64 has several benefits compared to K32:<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Can manage more than 32 GB RAM, as the <a href="/wiki/Memory_map" title="Memory map">memory map</a> would consume a disproportionately large area of the 32-bit kernel space.</li> <li>Cache buffer sizes can be larger than what the 32-bit kernel space allows, potentially increasing I/O performance.</li> <li>Performance is increased when using high-performance networking devices or multiple <a href="/wiki/Graphics_processing_unit" title="Graphics processing unit">graphics processing units</a> (GPUs), as the kernel can map all of the devices in 64-bit space even if several have very large <a href="/wiki/Direct_memory_access" title="Direct memory access">direct memory access</a> (DMA) buffers.</li></ul> <p>Booting while holding down <i>6</i> and <i>4</i> forces the machine to boot K64 on machines supporting 64-bit kernels.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> K64 will run 32-bit applications but it will not run 32-bit <a href="/wiki/Loadable_kernel_module" title="Loadable kernel module">kernel extensions</a> (KEXTs), so these must be ported to K64 to be able to load. </p><p>XNU in <a href="/wiki/OS_X_Mountain_Lion" title="OS X Mountain Lion">OS X Mountain Lion</a> (10.8) and later only provides a 64-bit kernel. </p> <div class="mw-heading mw-heading3"><h3 id="IOKit">IOKit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=5" title="Edit section: IOKit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>IOKit is the <a href="/wiki/Device_driver" title="Device driver">device driver</a> framework, written in a subset of <a href="/wiki/C%2B%2B" title="C++">C++</a> based on <a href="/wiki/Embedded_C%2B%2B" title="Embedded C++">Embedded C++</a>.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> Using its <a href="/wiki/Object-oriented_programming" title="Object-oriented programming">object-oriented</a> design, features common to any class of driver are provided within the framework, helping device drivers be written in less time and code. IOKit is multi-threaded, <a href="/wiki/Symmetric_multiprocessing" title="Symmetric multiprocessing">symmetric multiprocessing</a> (SMP)-safe, and allows for hot-pluggable devices and automatic, dynamic device configuration. </p><p>Many drivers can be written to run in <a href="/wiki/User_space_and_kernel_space" title="User space and kernel space">user mode</a>, which further enhances the stability of the system. If a driver running in user mode crashes, it will not crash the kernel. However, if a driver running in kernel mode crashes it will crash the kernel. Examples of drivers running in kernel mode include disk adapter and network adapter drivers, graphics drivers, drivers for Universal Serial Bus (<a href="/wiki/USB" title="USB">USB</a>) and <a href="/wiki/FireWire" class="mw-redirect" title="FireWire">FireWire</a> <a href="/wiki/Host_controller_interface_(USB,_Firewire)" title="Host controller interface (USB, Firewire)">host controllers</a>, and drivers for <a href="/wiki/Virtual_machine" title="Virtual machine">virtual machine</a> software such as <a href="/wiki/VirtualBox" title="VirtualBox">VirtualBox</a>, <a href="/wiki/Parallels_Desktop_for_Mac" title="Parallels Desktop for Mac">Parallels Desktop for Mac</a>, and <a href="/wiki/VMware_Fusion" title="VMware Fusion">VMware Fusion</a>. In <a href="/wiki/MacOS_Catalina" title="MacOS Catalina">macOS Catalina</a> and later releases, DriverKit allows some of those types of drivers to run in user mode.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=6" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1266661725">.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output .portalbox-entry{display:table-row;font-size:85%;line-height:110%;height:1.9em;font-style:italic;font-weight:bold}.mw-parser-output .portalbox-image{display:table-cell;padding:0.2em;vertical-align:middle;text-align:center}.mw-parser-output .portalbox-link{display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle}@media(min-width:720px){.mw-parser-output .portalleft{margin:0.5em 1em 0.5em 0}.mw-parser-output .portalright{clear:right;float:right;margin:0.5em 0 0.5em 1em}}</style><ul role="navigation" aria-label="Portals" class="noprint portalbox portalborder portalright"> <li class="portalbox-entry"><span class="portalbox-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/28px-Free_and_open-source_software_logo_%282009%29.svg.png" decoding="async" width="28" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/42px-Free_and_open-source_software_logo_%282009%29.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/56px-Free_and_open-source_software_logo_%282009%29.svg.png 2x" data-file-width="512" data-file-height="512" /></span></span></span><span class="portalbox-link"><a href="/wiki/Portal:Free_and_open-source_software" title="Portal:Free and open-source software">Free and open-source software portal</a></span></li></ul> <ul><li><a href="/wiki/Kernel_(operating_system)" title="Kernel (operating system)">Kernel (operating system)</a></li> <li><a href="/wiki/A/UX" title="A/UX">A/UX</a></li> <li><a href="/wiki/MkLinux" title="MkLinux">mkLinux</a></li> <li><a href="/wiki/OSF/1" title="OSF/1">OSF/1</a></li> <li><a href="/wiki/Darwin_(operating_system)" title="Darwin (operating system)">Darwin (operating system)</a> – open source operating system released by Apple, Inc., with XNU as kernel</li> <li><a href="/wiki/MacOS" title="MacOS">macOS</a> – operating system released by Apple, Inc., with XNU as kernel</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=7" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external free" href="https://fahrplan.events.ccc.de/congress/2007/Fahrplan/attachments/986_inside_the_mac_osx_kernel.pdf">https://fahrplan.events.ccc.de/congress/2007/Fahrplan/attachments/986_inside_the_mac_osx_kernel.pdf</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://developer.apple.com/library/content/documentation/Porting/Conceptual/PortingUnix/glossary/glossary.html">"Porting UNIX/Linux Applications to Mac OS X: Glossary"</a>. Apple Computer. 2005<span class="reference-accessdate">. Retrieved <span class="nowrap">June 7,</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Porting+UNIX%2FLinux+Applications+to+Mac+OS+X%3A+Glossary&rft.pub=Apple+Computer&rft.date=2005&rft_id=https%3A%2F%2Fdeveloper.apple.com%2Flibrary%2Fcontent%2Fdocumentation%2FPorting%2FConceptual%2FPortingUnix%2Fglossary%2Fglossary.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://github.com/apple/darwin-xnu">"XNU GitHub source code README"</a>. <i><a href="/wiki/GitHub" title="GitHub">GitHub</a></i>. December 16, 2021.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=GitHub&rft.atitle=XNU+GitHub+source+code+README&rft.date=2021-12-16&rft_id=https%3A%2F%2Fgithub.com%2Fapple%2Fdarwin-xnu&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-wwdc-2000-session-106-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-wwdc-2000-session-106_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-wwdc-2000-session-106_4-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFMagee" class="citation audio-visual cs1">Magee, Jim. <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=ggnFoDqzGMU"><i>WWDC 2000 Session 106 – Mac OS X: Kernel</i></a>. 14 minutes in. <a rel="nofollow" class="external text" href="https://ghostarchive.org/varchive/youtube/20211221/ggnFoDqzGMU">Archived</a> from the original on December 21, 2021.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=WWDC+2000+Session+106+%E2%80%93+Mac+OS+X%3A+Kernel&rft.aulast=Magee&rft.aufirst=Jim&rft_id=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DggnFoDqzGMU&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://developer.apple.com/library/mac/documentation/DeviceDrivers/Conceptual/WritingDeviceDriver/CPluPlusRuntime/CPlusPlusRuntime.html#//apple_ref/doc/uid/TP30000695-BAJIBFDE">"The libkern C++ Runtime"</a>. <i>IOKit Device Driver Design Guidelines</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IOKit+Device+Driver+Design+Guidelines&rft.atitle=The+libkern+C%2B%2B+Runtime&rft_id=https%3A%2F%2Fdeveloper.apple.com%2Flibrary%2Fmac%2Fdocumentation%2FDeviceDrivers%2FConceptual%2FWritingDeviceDriver%2FCPluPlusRuntime%2FCPlusPlusRuntime.html%23%2F%2Fapple_ref%2Fdoc%2Fuid%2FTP30000695-BAJIBFDE&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFAmit_Singh" class="citation web cs1">Amit Singh. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190419152142/http://osxbook.com/book/bonus/ancient/whatismacosx/arch_xnu.html">"What is Mac OS X?"</a>. Archived from <a rel="nofollow" class="external text" href="http://osxbook.com/book/bonus/ancient/whatismacosx/arch_xnu.html">the original</a> on April 19, 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">March 4,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=What+is+Mac+OS+X%3F&rft.au=Amit+Singh&rft_id=http%3A%2F%2Fosxbook.com%2Fbook%2Fbonus%2Fancient%2Fwhatismacosx%2Farch_xnu.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://computer.howstuffworks.com/macs/mac-os-x2.htm">"How Mac OS X Works"</a>. <i>HowStuffWorks</i>. August 8, 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">March 12,</span> 2025</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=HowStuffWorks&rft.atitle=How+Mac+OS+X+Works&rft.date=2011-08-08&rft_id=https%3A%2F%2Fcomputer.howstuffworks.com%2Fmacs%2Fmac-os-x2.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFMcKay2019" class="citation web cs1">McKay, Dave (October 21, 2019). <a rel="nofollow" class="external text" href="https://www.howtogeek.com/441599/is-macos-unix-and-what-does-that-mean/">"Is macOS UNIX? (and What Does That Mean?)"</a>. <i>How-To Geek</i><span class="reference-accessdate">. Retrieved <span class="nowrap">March 12,</span> 2025</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=How-To+Geek&rft.atitle=Is+macOS+UNIX%3F+%28and+What+Does+That+Mean%3F%29&rft.date=2019-10-21&rft.aulast=McKay&rft.aufirst=Dave&rft_id=https%3A%2F%2Fwww.howtogeek.com%2F441599%2Fis-macos-unix-and-what-does-that-mean%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation news cs1"><a rel="nofollow" class="external text" href="http://web.archive.org/web/20250124104637/https://www.theregister.com/2024/10/11/macos_15_is_unix/">"Apple macOS 15 Sequoia is officially UNIX"</a>. Archived from <a rel="nofollow" class="external text" href="https://www.theregister.com/2024/10/11/macos_15_is_unix/">the original</a> on January 24, 2025<span class="reference-accessdate">. Retrieved <span class="nowrap">March 12,</span> 2025</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Apple+macOS+15+Sequoia+is+officially+UNIX&rft_id=https%3A%2F%2Fwww.theregister.com%2F2024%2F10%2F11%2Fmacos_15_is_unix%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFWells1994" class="citation conference cs1">Wells, Douglas M. (1994). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170822053715/https://pdfs.semanticscholar.org/03ac/1296f530719497b49d7580b55a2d9b8353ab.pdf"><i>A Trusted, Scalable, Real-Time Operating System Environment</i></a> <span class="cs1-format">(PDF)</span>. 1994 IEEE Dual-Use Technologies and Applications Conference. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:5205380">5205380</a>. Archived from <a rel="nofollow" class="external text" href="https://pdfs.semanticscholar.org/03ac/1296f530719497b49d7580b55a2d9b8353ab.pdf">the original</a> <span class="cs1-format">(PDF)</span> on August 22, 2017.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=A+Trusted%2C+Scalable%2C+Real-Time+Operating+System+Environment&rft.date=1994&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A5205380%23id-name%3DS2CID&rft.aulast=Wells&rft.aufirst=Douglas+M.&rft_id=https%3A%2F%2Fpdfs.semanticscholar.org%2F03ac%2F1296f530719497b49d7580b55a2d9b8353ab.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFWatson2008" class="citation mailinglist cs1"><a href="/wiki/Robert_Watson_(computer_scientist)" title="Robert Watson (computer scientist)">Watson, Robert</a> (August 2, 2008). <a rel="nofollow" class="external text" href="http://lists.freebsd.org/pipermail/freebsd-advocacy/2008-August/003674.html">"Re: freebsd-advocacy Digest, Vol 248, Issue 1"</a>. <i>freebsd-advocacy</i> (Mailing list)<span class="reference-accessdate">. Retrieved <span class="nowrap">October 24,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Re%3A+freebsd-advocacy+Digest%2C+Vol+248%2C+Issue+1&rft.date=2008-08-02&rft.aulast=Watson&rft.aufirst=Robert&rft_id=http%3A%2F%2Flists.freebsd.org%2Fpipermail%2Ffreebsd-advocacy%2F2008-August%2F003674.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.freebsd.org/news/status/report-2009-04-2009-09.html#Grand-Central-Dispatch---FreeBSD-port">"FreeBSD Quarterly Status Report (Grand Central Dispatch – FreeBSD port)"</a>. April 2009<span class="reference-accessdate">. Retrieved <span class="nowrap">October 24,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=FreeBSD+Quarterly+Status+Report+%28Grand+Central+Dispatch+%E2%80%93+FreeBSD+port%29&rft.date=2009-04&rft_id=http%3A%2F%2Fwww.freebsd.org%2Fnews%2Fstatus%2Freport-2009-04-2009-09.html%23Grand-Central-Dispatch---FreeBSD-port&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://arstechnica.com/apple/reviews/2009/08/mac-os-x-10-6.ars/5">Mac OS X 10.6 Snow Leopard: the Ars Technica review, page 5</a></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFSiracusa2009" class="citation web cs1">Siracusa, John (August 31, 2009). <a rel="nofollow" class="external text" href="https://arstechnica.com/apple/2009/08/mac-os-x-10-6/5/">"Mac OS X 10.6 Snow Leopard: the Ars Technica review"</a>. <i><a href="/wiki/Ars_Technica" title="Ars Technica">Ars Technica</a></i>. <q>Finally, this is worth repeating: please keep in mind that you do not need to run the 64-bit kernel in order to run 64-bit applications or install more than 4 GB of RAM in your Mac. Applications run just fine in 64-bit mode on top of the 32-bit kernel, and even in earlier versions of Mac OS X it's been possible to install and take advantage of much more than 4GB of RAM.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Ars+Technica&rft.atitle=Mac+OS+X+10.6+Snow+Leopard%3A+the+Ars+Technica+review&rft.date=2009-08-31&rft.aulast=Siracusa&rft.aufirst=John&rft_id=https%3A%2F%2Farstechnica.com%2Fapple%2F2009%2F08%2Fmac-os-x-10-6%2F5%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://support.apple.com/kb/HT3770">Mac OS X Server v10.6: Macs that use the 64-bit kernel</a></span> </li> <li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://developer.apple.com/mac/library/releasenotes/MacOSX/WhatsNewInOSX/Articles/MacOSX10_6.html">"What's New in Mac OS X: Mac OS X v10.6"</a>. <i>Apple Developer</i>. Apple, Inc.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Apple+Developer&rft.atitle=What%27s+New+in+Mac+OS+X%3A+Mac+OS+X+v10.6&rft_id=https%3A%2F%2Fdeveloper.apple.com%2Fmac%2Flibrary%2Freleasenotes%2FMacOSX%2FWhatsNewInOSX%2FArticles%2FMacOSX10_6.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://support.apple.com/kb/HT3773">Mac OS X Server v10.6: Starting up with the 32-bit or 64-bit kernel</a></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFAmit_Singh" class="citation web cs1">Amit Singh. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190419152142/http://osxbook.com/book/bonus/ancient/whatismacosx/arch_xnu.html">"XNU: The Kernel"</a>. <i>What is Mac OS X?</i>. I/O Kit. Archived from <a rel="nofollow" class="external text" href="http://osxbook.com/book/bonus/ancient/whatismacosx/arch_xnu.html">the original</a> on April 19, 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">September 9,</span> 2011</span>. <q>I/O Kit uses a restricted subset of C++</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=What+is+Mac+OS+X%3F&rft.atitle=XNU%3A+The+Kernel&rft.pages=I%2FO+Kit&rft.au=Amit+Singh&rft_id=http%3A%2F%2Fosxbook.com%2Fbook%2Fbonus%2Fancient%2Fwhatismacosx%2Farch_xnu.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://developer.apple.com/documentation/driverkit">"DriverKit"</a>. <i>Apple Developer</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Apple+Developer&rft.atitle=DriverKit&rft_id=https%3A%2F%2Fdeveloper.apple.com%2Fdocumentation%2Fdriverkit&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXNU" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XNU&action=edit&section=8" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="https://github.com/apple-oss-distributions/xnu">xnu</a> on <a href="/wiki/GitHub" title="GitHub">GitHub</a>, official repository</li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20200602233536/http://osxbook.com/book/bonus/ancient/whatismacosx/arch_xnu.html">XNU: The Kernel</a> at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> (archived June 2, 2020) – an overview of the components of XNU, written by Amit Singh in December 2003</li> <li><a rel="nofollow" class="external text" href="https://media.ccc.de/v/24c3-2303-en-inside_the_macosx_kernel">Inside the Mac OS X Kernel</a> – "This talk intends to clear up the confusion by presenting details of the Mac OS X kernel" (December 2007)</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl 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tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Operating_systems_by_Apple405" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Apple_operating_systems" title="Template:Apple operating systems"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Apple_operating_systems" title="Template talk:Apple operating systems"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Apple_operating_systems" title="Special:EditPage/Template:Apple operating systems"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Operating_systems_by_Apple405" style="font-size:114%;margin:0 4em">Operating systems by <a href="/wiki/Apple_Inc." title="Apple Inc.">Apple</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Apple_II" title="Apple II">Apple II</a>, <a href="/wiki/Apple_III" title="Apple III">III</a>, <a href="/wiki/Apple_Lisa" title="Apple Lisa">Lisa</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apple_II" title="Apple II">Apple II</a> <ul><li><a href="/wiki/Apple_DOS" title="Apple DOS">Apple DOS</a></li> <li><a href="/wiki/Apple_ProDOS" title="Apple ProDOS">ProDOS</a></li> <li><a href="/wiki/Apple_GS/OS" title="Apple GS/OS">GS/OS</a></li></ul></li> <li><a href="/wiki/Apple_III" title="Apple III">Apple III</a> <ul><li><a href="/wiki/Apple_SOS" title="Apple SOS">SOS</a></li></ul></li> <li><a href="/wiki/Apple_Lisa" title="Apple Lisa">Lisa</a> <ul><li><a href="/wiki/Apple_Lisa#Software" title="Apple Lisa">Lisa OS</a></li> <li><a href="/wiki/MacWorks_XL" title="MacWorks XL">MacWorks</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Mac_operating_systems" title="Mac operating systems">Mac</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Classic_Mac_OS" title="Classic Mac OS">Classic Mac OS</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/System_1" title="System 1">System 1</a></li> <li><a href="/wiki/Classic_Mac_OS#System_1,_2,_3,_and_4" title="Classic Mac OS">Systems 2, 3, and 4</a></li> <li><a href="/wiki/Classic_Mac_OS#System_Software_5" title="Classic Mac OS">System 5</a></li> <li><a href="/wiki/System_6" title="System 6">System 6</a></li> <li><a href="/wiki/System_7" title="System 7">System 7</a></li> <li><a href="/wiki/Mac_OS_8" title="Mac OS 8">Mac OS 8</a></li> <li><a href="/wiki/Mac_OS_9" title="Mac OS 9">Mac OS 9</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/MacOS" title="MacOS">macOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MacOS_version_history" title="MacOS version history">History</a> <ul><li><a href="/wiki/NeXTSTEP" title="NeXTSTEP">NeXTSTEP</a></li> <li><a href="/wiki/OpenStep" title="OpenStep">OpenStep</a></li> <li><a href="/wiki/Rhapsody_(operating_system)" title="Rhapsody (operating system)">Rhapsody</a></li> <li><a href="/wiki/Mac_OS_X_Public_Beta" title="Mac OS X Public Beta">Public Beta</a></li></ul></li> <li>Core <ul><li><a href="/wiki/Darwin_(operating_system)" title="Darwin (operating system)">Darwin</a> <ul><li><a class="mw-selflink selflink">XNU</a></li></ul></li></ul></li> <li>Desktop <ul><li>Mac OS X <ul><li><a href="/wiki/Mac_OS_X_Public_Beta" title="Mac OS X Public Beta">Public Beta</a></li> <li><a href="/wiki/Mac_OS_X_10.0" title="Mac OS X 10.0">10.0 (Cheetah)</a></li> <li><a href="/wiki/Mac_OS_X_10.1" title="Mac OS X 10.1">10.1 (Puma)</a></li> <li><a href="/wiki/Mac_OS_X_Jaguar" title="Mac OS X Jaguar">10.2 Jaguar</a></li> <li><a href="/wiki/Mac_OS_X_Panther" title="Mac OS X Panther">10.3 Panther</a></li> <li><a href="/wiki/Mac_OS_X_Tiger" title="Mac OS X Tiger">10.4 Tiger</a></li> <li><a href="/wiki/Mac_OS_X_Leopard" title="Mac OS X Leopard">10.5 Leopard</a></li> <li><a href="/wiki/Mac_OS_X_Snow_Leopard" title="Mac OS X Snow Leopard">10.6 Snow Leopard</a></li> <li><a href="/wiki/Mac_OS_X_Lion" class="mw-redirect" title="Mac OS X Lion">10.7 Lion</a></li></ul></li> <li>OS X <ul><li><a href="/wiki/OS_X_Mountain_Lion" title="OS X Mountain Lion">10.8 Mountain Lion</a></li> <li><a href="/wiki/OS_X_Mavericks" title="OS X Mavericks">10.9 Mavericks</a></li> <li><a href="/wiki/OS_X_Yosemite" title="OS X Yosemite">10.10 Yosemite</a></li> <li><a href="/wiki/OS_X_El_Capitan" title="OS X El Capitan">10.11 El Capitan</a></li></ul></li> <li>macOS <ul><li><a href="/wiki/MacOS_Sierra" title="MacOS Sierra">10.12 Sierra</a></li> <li><a href="/wiki/MacOS_High_Sierra" title="MacOS High Sierra">10.13 High Sierra</a></li> <li><a href="/wiki/MacOS_Mojave" title="MacOS Mojave">10.14 Mojave</a></li> <li><a href="/wiki/MacOS_Catalina" title="MacOS Catalina">10.15 Catalina</a></li> <li><a href="/wiki/MacOS_Big_Sur" title="MacOS Big Sur">11 Big Sur</a></li> <li><a href="/wiki/MacOS_Monterey" title="MacOS Monterey">12 Monterey</a></li> <li><a href="/wiki/MacOS_Ventura" title="MacOS Ventura">13 Ventura</a></li> <li><a href="/wiki/MacOS_Sonoma" title="MacOS Sonoma">14 Sonoma</a></li> <li><a href="/wiki/MacOS_Sequoia" title="MacOS Sequoia">15 Sequoia</a></li></ul></li></ul></li> <li><a href="/wiki/MacOS_Server" class="mw-redirect" title="MacOS Server">Server</a> <ul><li><a href="/wiki/Mac_OS_X_Server_1.0" title="Mac OS X Server 1.0">Mac OS X Server 1.0</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other projects</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Shipped <ul><li><a href="/wiki/A/ROSE" title="A/ROSE">A/ROSE</a></li> <li><a href="/wiki/A/UX" title="A/UX">A/UX</a></li> <li><a href="/wiki/AIX_for_Apple_Network_Servers" class="mw-redirect" title="AIX for Apple Network Servers">AIX for Apple Network Servers</a></li> <li><a href="/wiki/Macintosh_Application_Environment" title="Macintosh Application Environment">MAE</a></li> <li><a href="/wiki/MkLinux" title="MkLinux">MkLinux</a></li> <li><a href="/wiki/PowerOpen_Environment" title="PowerOpen Environment">PowerOpen Environment</a></li></ul></li> <li>Cancelled <ul><li><a href="/wiki/Star_Trek_project" title="Star Trek project">Star Trek</a></li> <li><a href="/wiki/Taligent" title="Taligent">Taligent</a></li> <li><a href="/wiki/Copland_(operating_system)" title="Copland (operating system)">Copland</a> <ul><li><a href="/wiki/Nukernel" title="Nukernel">Nukernel</a></li></ul></li> <li><a href="/wiki/Vanguard_(microkernel)" title="Vanguard (microkernel)">Vanguard</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/IOS" title="IOS">iOS</a> derivatives</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/IOS" title="IOS">iOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>iPhone OS <ul><li><a href="/wiki/IPhone_OS_1" title="IPhone OS 1">1</a></li> <li><a href="/wiki/IPhone_OS_2" title="IPhone OS 2">2</a></li> <li><a href="/wiki/IPhone_OS_3" title="IPhone OS 3">3</a></li></ul></li> <li>iOS <ul><li><a href="/wiki/IOS_4" title="IOS 4">4</a></li> <li><a href="/wiki/IOS_5" title="IOS 5">5</a></li> <li><a href="/wiki/IOS_6" title="IOS 6">6</a></li> <li><a href="/wiki/IOS_7" title="IOS 7">7</a></li> <li><a href="/wiki/IOS_8" title="IOS 8">8</a></li> <li><a href="/wiki/IOS_9" title="IOS 9">9</a></li> <li><a href="/wiki/IOS_10" title="IOS 10">10</a></li> <li><a href="/wiki/IOS_11" title="IOS 11">11</a></li> <li><a href="/wiki/IOS_12" title="IOS 12">12</a></li> <li><a href="/wiki/IOS_13" title="IOS 13">13</a></li> <li><a href="/wiki/IOS_14" title="IOS 14">14</a></li> <li><a href="/wiki/IOS_15" title="IOS 15">15</a></li> <li><a href="/wiki/IOS_16" title="IOS 16">16</a></li> <li><a href="/wiki/IOS_17" title="IOS 17">17</a></li> <li><a href="/wiki/IOS_18" title="IOS 18">18</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/IPadOS" title="IPadOS">iPadOS</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IPadOS_13" title="IPadOS 13">13</a></li> <li><a href="/wiki/IPadOS_14" title="IPadOS 14">14</a></li> <li><a href="/wiki/IPadOS_15" title="IPadOS 15">15</a></li> <li><a href="/wiki/IPadOS_16" title="IPadOS 16">16</a></li> <li><a href="/wiki/IPadOS_17" title="IPadOS 17">17</a></li> <li><a href="/wiki/IPadOS_18" title="IPadOS 18">18</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Others</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/TvOS" title="TvOS">tvOS</a> <ul><li><a href="/wiki/Apple_TV#Software" title="Apple TV">Apple TV Software</a></li></ul></li> <li><a href="/wiki/VisionOS" title="VisionOS">visionOS</a></li> <li><a href="/wiki/WatchOS" title="WatchOS">watchOS</a></li> <li><a href="/wiki/AudioOS" class="mw-redirect" title="AudioOS">audioOS</a></li> <li><a href="/wiki/BridgeOS" title="BridgeOS">bridgeOS</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Others</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Newton_OS" title="Newton OS">Newton OS</a></li> <li><a href="/wiki/History_of_iTunes#Devices" title="History of iTunes">iPod software</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><span class="noviewer" typeof="mw:File"><span title="List-Class article"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/16px-Symbol_list_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/23px-Symbol_list_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/31px-Symbol_list_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/List_of_Apple_operating_systems" title="List of Apple operating systems">List</a> • <span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Apple_Inc._operating_systems" title="Category:Apple Inc. operating systems">Category</a></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Darwin-derived_operating_systems463" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Darwin_derivations" title="Template:Darwin derivations"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Darwin_derivations" title="Template talk:Darwin derivations"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Darwin_derivations" title="Special:EditPage/Template:Darwin derivations"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Darwin-derived_operating_systems463" style="font-size:114%;margin:0 4em"><a href="/wiki/Darwin_(operating_system)" title="Darwin (operating system)">Darwin</a>-<a href="/wiki/Darwin_(operating_system)#Derived_projects" title="Darwin (operating system)">derived</a> <a href="/wiki/List_of_Apple_operating_systems" title="List of Apple operating systems">operating systems</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Mac_operating_systems" title="Mac operating systems">History</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Unix" title="Unix">Unix</a></li> <li><a href="/wiki/Berkeley_Software_Distribution" title="Berkeley Software Distribution">BSD</a></li> <li><a href="/wiki/Mach_(kernel)" title="Mach (kernel)">Mach</a></li> <li><a href="/wiki/NeXTSTEP" title="NeXTSTEP">NeXTSTEP</a></li> <li><a href="/wiki/OpenStep" title="OpenStep">OpenStep</a> <ul><li><a href="/wiki/GNUstep" title="GNUstep">GNUstep</a></li></ul></li> <li><a href="/wiki/Rhapsody_(operating_system)" title="Rhapsody (operating system)">Rhapsody</a></li> <li><a href="/wiki/Classic_Mac_OS" title="Classic Mac OS">Classic Mac OS</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/MacOS" title="MacOS">macOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Mac OS X <ul><li><a href="/wiki/Mac_OS_X_Public_Beta" title="Mac OS X Public Beta">Public Beta</a></li> <li><a href="/wiki/Mac_OS_X_10.0" title="Mac OS X 10.0">10.0 (Cheetah)</a></li> <li><a href="/wiki/Mac_OS_X_10.1" title="Mac OS X 10.1">10.1 (Puma)</a></li> <li><a href="/wiki/Mac_OS_X_Jaguar" title="Mac OS X Jaguar">10.2 Jaguar</a></li> <li><a href="/wiki/Mac_OS_X_Panther" title="Mac OS X Panther">10.3 Panther</a></li> <li><a href="/wiki/Mac_OS_X_Tiger" title="Mac OS X Tiger">10.4 Tiger</a></li> <li><a href="/wiki/Mac_OS_X_Leopard" title="Mac OS X Leopard">10.5 Leopard</a></li> <li><a href="/wiki/Mac_OS_X_Snow_Leopard" title="Mac OS X Snow Leopard">10.6 Snow Leopard</a></li> <li><a href="/wiki/Mac_OS_X_Lion" class="mw-redirect" title="Mac OS X Lion">10.7 Lion</a></li></ul></li> <li>OS X <ul><li><a href="/wiki/OS_X_Mountain_Lion" title="OS X Mountain Lion">OS X 10.8 Mountain Lion</a></li> <li><a href="/wiki/OS_X_Mavericks" title="OS X Mavericks">10.9 Mavericks</a></li> <li><a href="/wiki/OS_X_Yosemite" title="OS X Yosemite">10.10 Yosemite</a></li> <li><a href="/wiki/OS_X_El_Capitan" title="OS X El Capitan">10.11 El Capitan</a></li></ul></li> <li>macOS <ul><li><a href="/wiki/MacOS_Sierra" title="MacOS Sierra">macOS 10.12 Sierra</a></li> <li><a href="/wiki/MacOS_High_Sierra" title="MacOS High Sierra">10.13 High Sierra</a></li> <li><a href="/wiki/MacOS_Mojave" title="MacOS Mojave">10.14 Mojave</a></li> <li><a href="/wiki/MacOS_Catalina" title="MacOS Catalina">10.15 Catalina</a></li> <li><a href="/wiki/MacOS_Big_Sur" title="MacOS Big Sur">11 Big Sur</a></li> <li><a href="/wiki/MacOS_Monterey" title="MacOS Monterey">12 Monterey</a></li> <li><a href="/wiki/MacOS_Ventura" title="MacOS Ventura">13 Ventura</a></li> <li><a href="/wiki/MacOS_Sonoma" title="MacOS Sonoma">14 Sonoma</a></li> <li><a href="/wiki/MacOS_Sequoia" title="MacOS Sequoia">15 Sequoia</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Mac_OS_X_Server" title="Mac OS X Server">Mac OS X<br />Server</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Mac_OS_X_Server_1.0" title="Mac OS X Server 1.0">1.0 (Hera)</a> <ul><li><a href="/wiki/Rhapsody_(operating_system)" title="Rhapsody (operating system)">Rhapsody</a></li></ul></li> <li><a href="/wiki/Mac_OS_X_Server_10.0" class="mw-redirect" title="Mac OS X Server 10.0">10.0 (Cheetah)</a></li> <li><a href="/wiki/Mac_OS_X_Server_10.1" class="mw-redirect" title="Mac OS X Server 10.1">10.1 (Puma)</a></li> <li><a href="/wiki/Mac_OS_X_Server_10.2" class="mw-redirect" title="Mac OS X Server 10.2">10.2 (Jaguar)</a></li> <li><a href="/wiki/Mac_OS_X_Server_10.3" class="mw-redirect" title="Mac OS X Server 10.3">10.3 (Panther)</a></li> <li><a href="/wiki/Mac_OS_X_Server_10.4" class="mw-redirect" title="Mac OS X Server 10.4">10.4 (Tiger)</a></li> <li><a href="/wiki/Mac_OS_X_Server_10.5" class="mw-redirect" title="Mac OS X Server 10.5">10.5 Leopard Server</a></li> <li><a href="/wiki/Mac_OS_X_Server_10.6" class="mw-redirect" title="Mac OS X Server 10.6">10.6 Snow Leopard Server</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Apple_TV_Software" class="mw-redirect" title="Apple TV Software">TV Software</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apple_TV_Software_1" class="mw-redirect" title="Apple TV Software 1">1</a></li> <li><a href="/wiki/Apple_TV_Software_2" class="mw-redirect" title="Apple TV Software 2">2</a></li> <li><a href="/wiki/Apple_TV_Software_3" class="mw-redirect" title="Apple TV Software 3">3</a></li> <li>Forks from iOS with 4</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/IOS" title="IOS">iOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>iPhone OS <ul><li><a href="/wiki/IPhone_OS_1" title="IPhone OS 1">1</a></li> <li><a href="/wiki/IPhone_OS_2" title="IPhone OS 2">2</a></li> <li><a href="/wiki/IPhone_OS_3" title="IPhone OS 3">3</a></li></ul></li> <li>iOS <ul><li><a href="/wiki/IOS_4" title="IOS 4">4</a></li> <li><a href="/wiki/IOS_5" title="IOS 5">5</a></li> <li><a href="/wiki/IOS_6" title="IOS 6">6</a></li> <li><a href="/wiki/IOS_7" title="IOS 7">7</a></li> <li><a href="/wiki/IOS_8" title="IOS 8">8</a></li> <li><a href="/wiki/IOS_9" title="IOS 9">9</a></li> <li><a href="/wiki/IOS_10" title="IOS 10">10</a></li> <li><a href="/wiki/IOS_11" title="IOS 11">11</a></li> <li><a href="/wiki/IOS_12" title="IOS 12">12</a></li> <li><a href="/wiki/IOS_13" title="IOS 13">13</a></li> <li><a href="/wiki/IOS_14" title="IOS 14">14</a></li> <li><a href="/wiki/IOS_15" title="IOS 15">15</a></li> <li><a href="/wiki/IOS_16" title="IOS 16">16</a></li> <li><a href="/wiki/IOS_17" title="IOS 17">17</a></li> <li><a href="/wiki/IOS_18" title="IOS 18">18</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/TvOS" title="TvOS">tvOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>TV Software <ul><li><a href="/wiki/Apple_TV_Software_4" class="mw-redirect" title="Apple TV Software 4">4</a></li> <li><a href="/wiki/Apple_TV_Software_5" class="mw-redirect" title="Apple TV Software 5">5</a></li> <li><a href="/wiki/Apple_TV_Software_6" class="mw-redirect" title="Apple TV Software 6">6</a></li> <li><a href="/wiki/Apple_TV_Software_7" class="mw-redirect" title="Apple TV Software 7">7</a></li></ul></li> <li>tvOS <ul><li><a href="/wiki/TvOS_9" class="mw-redirect" title="TvOS 9">9</a></li> <li><a href="/wiki/TvOS_10" class="mw-redirect" title="TvOS 10">10</a></li> <li><a href="/wiki/TvOS_11" class="mw-redirect" title="TvOS 11">11</a></li> <li><a href="/wiki/TvOS_12" class="mw-redirect" title="TvOS 12">12</a></li> <li><a href="/wiki/TvOS_13" class="mw-redirect" title="TvOS 13">13</a></li> <li><a href="/wiki/TvOS_14" class="mw-redirect" title="TvOS 14">14</a></li> <li><a href="/wiki/TvOS_15" class="mw-redirect" title="TvOS 15">15</a></li> <li><a href="/wiki/TvOS_16" class="mw-redirect" title="TvOS 16">16</a></li> <li><a href="/wiki/TvOS_17" class="mw-redirect" title="TvOS 17">17</a></li> <li><a href="/wiki/TvOS_18" class="mw-redirect" title="TvOS 18">18</a></li></ul></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="audioOS11" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/AudioOS" class="mw-redirect" title="AudioOS">audioOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AudioOS_13" class="mw-redirect" title="AudioOS 13">13.4</a></li> <li><a href="/w/index.php?title=AudioOS_14&action=edit&redlink=1" class="new" title="AudioOS 14 (page does not exist)">14</a></li> <li><a href="/w/index.php?title=AudioOS_15&action=edit&redlink=1" class="new" title="AudioOS 15 (page does not exist)">15</a></li> <li><a href="/w/index.php?title=AudioOS_16&action=edit&redlink=1" class="new" title="AudioOS 16 (page does not exist)">16</a></li> <li><a href="/w/index.php?title=AudioOS_17&action=edit&redlink=1" class="new" title="AudioOS 17 (page does not exist)">17</a></li> <li><a href="/w/index.php?title=AudioOS_18&action=edit&redlink=1" class="new" title="AudioOS 18 (page does not exist)">18</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/WatchOS" title="WatchOS">watchOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/WatchOS_1" class="mw-redirect" title="WatchOS 1">1</a></li> <li><a href="/wiki/WatchOS_2" class="mw-redirect" title="WatchOS 2">2</a></li> <li><a href="/wiki/WatchOS_3" class="mw-redirect" title="WatchOS 3">3</a></li> <li><a href="/wiki/WatchOS_4" class="mw-redirect" title="WatchOS 4">4</a></li> <li><a href="/wiki/WatchOS_5" class="mw-redirect" title="WatchOS 5">5</a></li> <li><a href="/wiki/WatchOS_6" class="mw-redirect" title="WatchOS 6">6</a></li> <li><a href="/wiki/WatchOS_7" class="mw-redirect" title="WatchOS 7">7</a></li> <li><a href="/wiki/WatchOS_8" class="mw-redirect" title="WatchOS 8">8</a></li> <li><a href="/wiki/WatchOS_9" class="mw-redirect" title="WatchOS 9">9</a></li> <li><a href="/wiki/WatchOS_10" class="mw-redirect" title="WatchOS 10">10</a></li> <li><a href="/wiki/WatchOS_11" class="mw-redirect" title="WatchOS 11">11</a></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="bridgeOS12" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/BridgeOS" title="BridgeOS">bridgeOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/BridgeOS_1" class="mw-redirect" title="BridgeOS 1">1</a></li> <li><a href="/wiki/BridgeOS_2" class="mw-redirect" title="BridgeOS 2">2</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/AudioOS" class="mw-redirect" title="AudioOS">audioOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AudioOS_11" class="mw-redirect" title="AudioOS 11">11</a></li> <li><a href="/wiki/AudioOS_12" class="mw-redirect" title="AudioOS 12">12</a></li> <li><a href="/wiki/AudioOS_13" class="mw-redirect" title="AudioOS 13">13</a></li> <li>Forks from tvOS with 13.4</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/IPadOS" title="IPadOS">iPadOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IPadOS_13" title="IPadOS 13">13</a></li> <li><a href="/wiki/IPadOS_14" title="IPadOS 14">14</a></li> <li><a href="/wiki/IPadOS_15" title="IPadOS 15">15</a></li> <li><a href="/wiki/IPadOS_16" title="IPadOS 16">16</a></li> <li><a href="/wiki/IPadOS_17" title="IPadOS 17">17</a></li> <li><a href="/wiki/IPadOS_18" title="IPadOS 18">18</a></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="visionOS12" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/VisionOS" title="VisionOS">visionOS</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/VisionOS_1" class="mw-redirect" title="VisionOS 1">1</a></li> <li><a href="/wiki/VisionOS_2" class="mw-redirect" title="VisionOS 2">2</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Non-Apple<br />distributions</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/OpenDarwin" class="mw-redirect" title="OpenDarwin">OpenDarwin</a></li> <li><a href="/wiki/PureDarwin" class="mw-redirect" title="PureDarwin">PureDarwin</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><a href="/wiki/MacOS_version_history" title="MacOS version history">macOS version history</a></li> <li><a href="/wiki/Mac_OS_X_Server_version_history" class="mw-redirect" title="Mac OS X Server version history">Mac OS X Server version history</a></li> <li><a href="/wiki/TvOS_version_history" class="mw-redirect" title="TvOS version history">tvOS version history</a></li> <li><a href="/wiki/IOS_version_history" title="IOS version history">iOS version history</a></li> <li><a href="/wiki/IPadOS_version_history" title="IPadOS version history">iPadOS version history</a></li> <li><a href="/wiki/WatchOS_version_history" class="mw-redirect" title="WatchOS version history">watchOS version history</a></li> <li><a href="/wiki/AudioOS_version_history" class="mw-redirect" title="AudioOS version history">audioOS version history</a><br /><i>Italics</i> denote upcoming products</li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Mobile_operating_systems880" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Mobile_operating_systems" title="Template:Mobile operating systems"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Mobile_operating_systems" title="Template talk:Mobile operating systems"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Mobile_operating_systems" title="Special:EditPage/Template:Mobile operating systems"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Mobile_operating_systems880" style="font-size:114%;margin:0 4em"><a href="/wiki/Mobile_operating_system" title="Mobile operating system">Mobile operating systems</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><a href="/wiki/Comparison_of_mobile_operating_systems" title="Comparison of mobile operating systems">Comparison</a></li> <li><a href="/wiki/List_of_open-source_mobile_phones" title="List of open-source mobile phones">Open-source mobile phones, OSes</a></li> <li><a href="/wiki/Open_Handset_Alliance" title="Open Handset Alliance">Open Handset Alliance</a></li> <li><a href="/wiki/Open_Mobile_Alliance" title="Open Mobile Alliance">Open Mobile Alliance</a></li> <li><a href="/wiki/List_of_mobile_app_distribution_platforms" title="List of mobile app distribution platforms">Mobile app distributions</a></li> <li><a href="/wiki/Mobile_app_development" title="Mobile app development">Mobile app development</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux" title="Linux">Linux</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_kernel" title="Linux kernel">Kernel</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><b>Active</b>: <a href="/wiki/Android_(operating_system)" title="Android (operating system)">Android</a> <ul><li><a href="/wiki/List_of_custom_Android_distributions" title="List of custom Android distributions">forks</a></li> <li><a href="/wiki/Android_Go" title="Android Go">Android Go</a></li> <li><a href="/wiki/Wear_OS" title="Wear OS">Wear OS</a></li></ul></li> <li><a href="/wiki/EMUI" title="EMUI">EMUI</a>, <a href="/wiki/HarmonyOS" title="HarmonyOS">HarmonyOS</a> (Linux kernel subsystem)</li> <li><a href="/wiki/ChromeOS" title="ChromeOS">ChromeOS</a> <ul><li><a href="/wiki/ChromeOS_Flex" class="mw-redirect" title="ChromeOS Flex">ChromeOS Flex</a></li></ul></li> <li><a href="/wiki/KaiOS" title="KaiOS">KaiOS</a> <ul><li><a href="/wiki/HMD_Global#Smart_Feature_OS" title="HMD Global">Smart Feature OS</a></li></ul></li> <li><a href="/wiki/Amazon_Kindle" title="Amazon Kindle">Kindle firmware</a></li> <li><a href="/wiki/LuneOS" title="LuneOS">LuneOS</a></li> <li><a href="/wiki/Maemo#Maemo_Leste" title="Maemo">Maemo Leste</a></li> <li><a href="/wiki/Tizen" title="Tizen">Tizen</a></li></ul> <ul><li><b>Defunct</b>: <a href="/wiki/Bada_(operating_system)" title="Bada (operating system)">Bada</a></li> <li><a href="/wiki/Firefox_OS" title="Firefox OS">Firefox OS</a> <ul><li><a href="/wiki/B2G_OS" class="mw-redirect" title="B2G OS">B2G OS</a></li></ul></li> <li><a href="/wiki/MeeGo" title="MeeGo">MeeGo</a></li> <li><a href="/wiki/MontaVista" title="MontaVista">MontaVista</a> <ul><li><a href="/wiki/MotoMagx" title="MotoMagx">MotoMagx</a></li> <li><a href="/wiki/Mobilinux" title="Mobilinux">Mobilinux</a></li></ul></li> <li><a href="/wiki/OpenEmbedded" title="OpenEmbedded">OpenEmbedded</a> <ul><li><a href="/wiki/%C3%85ngstr%C3%B6m_distribution" title="Ångström distribution">Ångström</a></li> <li><a href="/wiki/Openmoko_Linux" title="Openmoko Linux">Openmoko Linux</a></li> <li><a href="/wiki/QtMoko" class="mw-redirect" title="QtMoko">QtMoko</a></li> <li><a href="/wiki/SHR_(operating_system)" title="SHR (operating system)">SHR</a></li></ul></li> <li><a href="/wiki/OpenEZX" title="OpenEZX">OpenEZX</a></li> <li><a href="/wiki/WebOS" title="WebOS">WebOS</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/GNU" title="GNU">GNU</a>/<br /><a href="/wiki/Linux" title="Linux">Linux</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><b>Active</b>: <a href="/wiki/Fedora_Linux" title="Fedora Linux">Fedora Mobility</a></li> <li><a href="/wiki/Manjaro" title="Manjaro">Manjaro</a> ARM</li> <li><a href="/wiki/PostmarketOS" title="PostmarketOS">postmarketOS</a></li> <li><a href="/wiki/PureOS" title="PureOS">PureOS</a></li> <li><a href="/wiki/Sailfish_OS" title="Sailfish OS">Sailfish OS</a></li> <li><a href="/wiki/SteamOS" title="SteamOS">SteamOS</a></li> <li><a href="/wiki/Ubuntu_Touch" title="Ubuntu Touch">Ubuntu Touch</a> <ul><li><a href="/wiki/UBports" class="mw-redirect" title="UBports">UBports</a></li></ul></li> <li><a href="/wiki/Mobian" title="Mobian">Mobian</a></li></ul> <ul><li><b>Defunct</b>: <a href="/wiki/Maemo" title="Maemo">Maemo</a> <ul><li><a href="/wiki/Mer_(software_distribution)" title="Mer (software distribution)">Mer</a></li></ul></li> <li><a href="/wiki/Moblin" title="Moblin">Moblin</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a class="mw-selflink selflink">XNU</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IOS" title="IOS">iOS</a> <ul><li><a href="/wiki/IPadOS" title="IPadOS">iPadOS</a></li> <li><a href="/wiki/WatchOS" title="WatchOS">watchOS</a> <ul><li><a href="/wiki/BridgeOS" title="BridgeOS">bridgeOS</a></li></ul></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/QNX" title="QNX">QNX</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/BlackBerry_10" title="BlackBerry 10">BlackBerry 10</a></li> <li><a href="/wiki/BlackBerry_Tablet_OS" title="BlackBerry Tablet OS">BlackBerry Tablet OS</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Microsoft_Windows" title="Microsoft Windows">Microsoft<br />Windows</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Windows_XP_editions#Tablet_PC_Edition" title="Windows XP editions">Windows XP Tablet PC Edition</a></li> <li><a href="/wiki/Windows_Mobile" title="Windows Mobile">Windows Mobile</a></li> <li><a href="/wiki/Windows_Phone" title="Windows Phone">Windows Phone</a> <ul><li><a href="/wiki/Windows_Phone_7" title="Windows Phone 7">7</a></li> <li><a href="/wiki/Windows_Phone_8" title="Windows Phone 8">8</a></li> <li><a href="/wiki/Windows_Phone_8.1" title="Windows Phone 8.1">8.1</a></li></ul></li> <li><a href="/wiki/Windows_RT" title="Windows RT">Windows RT</a></li> <li><a href="/wiki/Windows_10_Mobile" title="Windows 10 Mobile">Windows 10 Mobile</a></li> <li><a href="/wiki/Windows_8" title="Windows 8">Windows 8</a> <ul><li><a href="/wiki/Windows_8.1" title="Windows 8.1">Windows 8.1</a></li></ul></li> <li><a href="/wiki/Windows_10" title="Windows 10">Windows 10</a></li> <li><a href="/wiki/Windows_11" title="Windows 11">Windows 11</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Zircon_(microkernel)" class="mw-redirect" title="Zircon (microkernel)">Zircon</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fuchsia_(operating_system)" title="Fuchsia (operating system)">Fuchsia</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/FreeBSD" title="FreeBSD">FreeBSD</a>, <a href="/wiki/NetBSD" title="NetBSD">NetBSD</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PlayStation_Vita_system_software" title="PlayStation Vita system software">PlayStation Vita system software</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/OpenHarmony" title="OpenHarmony">OpenHarmony</a>,<br /><a href="/wiki/HarmonyOS_NEXT" title="HarmonyOS NEXT">HarmonyOS NEXT</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><b>Active</b>: <a href="/wiki/OpenHarmony" title="OpenHarmony">OpenHarmony</a></li> <li><a href="/wiki/HarmonyOS" title="HarmonyOS">HarmonyOS</a> <ul><li><a href="/wiki/HarmonyOS_NEXT" title="HarmonyOS NEXT">HarmonyOS NEXT</a></li></ul></li></ul> <ul><li><b>Defunct</b>: <a href="/wiki/EMUI" title="EMUI">EMUI</a> (non GMS-based)</li> <li><a href="/wiki/LiteOS" title="LiteOS">LiteOS</a></li> <li>Huawei Band OS</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/FreeRTOS" title="FreeRTOS">FreeRTOS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Amazfit OS <ul><li>Zepp OS</li></ul></li> <li>MIUI Band OS</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Nintendo" title="Nintendo">Nintendo</a><br />system software</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nintendo_3DS_system_software" title="Nintendo 3DS system software">Nintendo 3DS system software</a></li> <li><a href="/wiki/Nintendo_DSi_system_software" title="Nintendo DSi system software">Nintendo DSi system software</a></li> <li><a href="/wiki/Nintendo_Switch_system_software" title="Nintendo Switch system software">Nintendo Switch system software</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Minix_3" title="Minix 3">Minix 3</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Intel_Management_Engine" title="Intel Management Engine">Intel Management Engine</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Symbian" title="Symbian">Symbian</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/S60_(software_platform)" title="S60 (software platform)">S60</a></li> <li><a href="/wiki/Series_80_(software_platform)" title="Series 80 (software platform)">S80</a></li> <li><a href="/wiki/Series_90_(software_platform)" title="Series 90 (software platform)">S90</a></li> <li><a href="/wiki/UIQ" title="UIQ">UIQ</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Others</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Binary_Runtime_Environment_for_Wireless" title="Binary Runtime Environment for Wireless">Binary Runtime Environment for Wireless</a> (BREW)</li> <li><a href="/wiki/BlackBerry_OS" title="BlackBerry OS">BlackBerry OS</a></li> <li><a href="/wiki/EPOC_(operating_system)" title="EPOC (operating system)">EPOC</a></li> <li><a href="/wiki/GEOS_(16-bit_operating_system)" title="GEOS (16-bit operating system)">GEOS</a></li> <li><a href="/wiki/Magic_Cap" title="Magic Cap">Magic Cap</a></li> <li><a href="/wiki/Nokia_Asha_platform" title="Nokia Asha platform">Nokia Asha platform</a></li> <li><a href="/wiki/PalmDOS" class="mw-redirect" title="PalmDOS">PalmDOS</a></li> <li><a href="/wiki/Palm_OS" title="Palm OS">Palm OS</a></li> <li><a href="/wiki/PlayStation_Portable_system_software" title="PlayStation Portable system software">PlayStation Portable system software</a></li> <li><a href="/wiki/Series_30" class="mw-redirect" title="Series 30">S30</a></li> <li><a href="/wiki/Series_30%2B" title="Series 30+">S30+</a></li> <li><a href="/wiki/Series_40" title="Series 40">S40</a></li> <li><a href="/wiki/Sony_Ericsson_Java_Platform" title="Sony Ericsson Java Platform">Sony Ericsson Java Platform</a></li> <li><a href="/wiki/ThreadX" title="ThreadX">ThreadX</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2"><div> <ul><li><a href="/wiki/Portal:Software" class="mw-redirect" title="Portal:Software">Software</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Mobile_operating_systems" title="Category:Mobile operating systems">Mobile operating systems</a></li> <li><a href="/wiki/Category:Mobile_applications" title="Category:Mobile applications">Mobile applications</a></li> <li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Symbol_portal_class.svg" class="mw-file-description" title="Portal"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/20px-Symbol_portal_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/40px-Symbol_portal_class.svg.png 1.5x" data-file-width="180" data-file-height="185" /></a></span> <a href="/wiki/Portal:Telecommunication" title="Portal:Telecommunication">Telecommunication</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="macOS408" style="padding:3px"><table class="nowraplinks hlist mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:MacOS" title="Template:MacOS"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:MacOS" title="Template talk:MacOS"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:MacOS" title="Special:EditPage/Template:MacOS"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="macOS408" style="font-size:114%;margin:0 4em"><a href="/wiki/MacOS" title="MacOS">macOS</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><a href="/wiki/MacOS_version_history" title="MacOS version history">History</a></li> <li><a href="/wiki/Architecture_of_macOS" title="Architecture of macOS">Architecture</a></li> <li><a href="/wiki/List_of_built-in_macOS_apps" title="List of built-in macOS apps">Built-in apps</a></li> <li><a href="/wiki/MacOS_Server" class="mw-redirect" title="MacOS Server">Server</a></li> <li><a href="/wiki/List_of_Mac_software" title="List of Mac software">Software</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Versions</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Mac_OS_X" class="mw-redirect" title="Mac OS X">Mac OS X</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Mac_OS_X_Server_1.0" title="Mac OS X Server 1.0">Server 1.0</a></li> <li><a href="/wiki/Mac_OS_X_Public_Beta" title="Mac OS X Public Beta">Public Beta</a></li> <li><a href="/wiki/Mac_OS_X_10.0" title="Mac OS X 10.0">10.0 Cheetah</a></li> <li><a href="/wiki/Mac_OS_X_10.1" title="Mac OS X 10.1">10.1 Puma</a></li> <li><a href="/wiki/Mac_OS_X_Jaguar" title="Mac OS X Jaguar">10.2 Jaguar</a></li> <li><a href="/wiki/Mac_OS_X_Panther" title="Mac OS X Panther">10.3 Panther</a></li> <li><a href="/wiki/Mac_OS_X_Tiger" title="Mac OS X Tiger">10.4 Tiger</a></li> <li><a href="/wiki/Mac_OS_X_Leopard" title="Mac OS X Leopard">10.5 Leopard</a></li> <li><a href="/wiki/Mac_OS_X_Snow_Leopard" title="Mac OS X Snow Leopard">10.6 Snow Leopard</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">OS X</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/OS_X_Lion" title="OS X Lion">10.7 Lion</a></li> <li><a href="/wiki/OS_X_Mountain_Lion" title="OS X Mountain Lion">10.8 Mountain Lion</a></li> <li><a href="/wiki/OS_X_Mavericks" title="OS X Mavericks">10.9 Mavericks</a></li> <li><a href="/wiki/OS_X_Yosemite" title="OS X Yosemite">10.10 Yosemite</a></li> <li><a href="/wiki/OS_X_El_Capitan" title="OS X El Capitan">10.11 El Capitan</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">macOS</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MacOS_Sierra" title="MacOS Sierra">10.12 Sierra</a></li> <li><a href="/wiki/MacOS_High_Sierra" title="MacOS High Sierra">10.13 High Sierra</a></li> <li><a href="/wiki/MacOS_Mojave" title="MacOS Mojave">10.14 Mojave</a></li> <li><a href="/wiki/MacOS_Catalina" title="MacOS Catalina">10.15 Catalina</a></li> <li><a href="/wiki/MacOS_Big_Sur" title="MacOS Big Sur">11 Big Sur</a></li> <li><a href="/wiki/MacOS_Monterey" title="MacOS Monterey">12 Monterey</a></li> <li><a href="/wiki/MacOS_Ventura" title="MacOS Ventura">13 Ventura</a></li> <li><a href="/wiki/MacOS_Sonoma" title="MacOS Sonoma">14 Sonoma</a></li> <li><a href="/wiki/MacOS_Sequoia" title="MacOS Sequoia">15 Sequoia</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Predecessors</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Classic_Mac_OS" title="Classic Mac OS">Classic Mac OS</a></li> <li><a href="/wiki/NeXTSTEP" title="NeXTSTEP">NeXTSTEP</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Applications</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Core Applications</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Mac_App_Store" title="Mac App Store">App Store</a></li> <li><a href="/wiki/Automator_(macOS)" title="Automator (macOS)">Automator</a></li> <li><a href="/wiki/Calculator_(Apple)" title="Calculator (Apple)">Calculator</a></li> <li><a href="/wiki/Calendar_(Apple)" title="Calendar (Apple)">Calendar</a></li> <li><a href="/wiki/List_of_built-in_macOS_apps#Chess" title="List of built-in macOS apps">Chess</a></li> <li><a href="/wiki/Contacts_(Apple)" title="Contacts (Apple)">Contacts</a></li> <li><a href="/wiki/Control_Center_(Apple)" title="Control Center (Apple)">Control Center</a></li> <li><a href="/wiki/Dictionary_(software)" title="Dictionary (software)">Dictionary</a></li> <li><a href="/wiki/DVD_Player_(macOS)" class="mw-redirect" title="DVD Player (macOS)">DVD Player</a></li> <li><a href="/wiki/FaceTime" title="FaceTime">FaceTime</a></li> <li><a href="/wiki/Finder_(software)" title="Finder (software)">Finder</a></li> <li><a href="/wiki/Game_Center" title="Game Center">Game Center</a></li> <li><a href="/wiki/Grapher" title="Grapher">Grapher</a></li> <li><a href="/wiki/HomeKit" class="mw-redirect" title="HomeKit">Home</a></li> <li><a href="/wiki/Launchpad_(macOS)" class="mw-redirect" title="Launchpad (macOS)">Launchpad</a></li> <li><a href="/wiki/Apple_Mail" title="Apple Mail">Mail</a></li> <li><a href="/wiki/Messages_(Apple)" title="Messages (Apple)">Messages</a></li> <li><a href="/wiki/Apple_News" title="Apple News">News</a></li> <li><a href="/wiki/Music_(software)" class="mw-redirect" title="Music (software)">Music</a></li> <li><a href="/wiki/Notes_(Apple)" title="Notes (Apple)">Notes</a></li> <li><a href="/wiki/Notification_Center" title="Notification Center">Notification Center</a></li> <li><a href="/wiki/Apple_Podcasts" title="Apple Podcasts">Podcasts</a></li> <li><a href="/wiki/Photo_Booth" title="Photo Booth">Photo Booth</a></li> <li><a href="/wiki/Photos_(Apple)" title="Photos (Apple)">Photos</a></li> <li><a href="/wiki/Preview_(macOS)" title="Preview (macOS)">Preview</a></li> <li><a href="/wiki/QuickTime" title="QuickTime">Quicktime Player</a></li> <li><a href="/wiki/Reminders_(Apple)" title="Reminders (Apple)">Reminders</a></li> <li><a href="/wiki/Safari_(web_browser)" title="Safari (web browser)">Safari</a> <ul><li><a href="/wiki/Safari_version_history" class="mw-redirect" title="Safari version history">version history</a></li></ul></li> <li><a href="/wiki/Shortcuts_(app)" class="mw-redirect" title="Shortcuts (app)">Shortcuts</a></li> <li><a href="/wiki/Siri" title="Siri">Siri</a></li> <li><a href="/wiki/Stickies_(Apple)" title="Stickies (Apple)">Stickies</a></li> <li><a href="/wiki/TextEdit" title="TextEdit">TextEdit</a></li> <li><a href="/wiki/Time_Machine_(macOS)" title="Time Machine (macOS)">Time Machine</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Apple_Developer_Tools" title="Apple Developer Tools">Developer Tools</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Xcode" title="Xcode">Xcode</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Instruments_(software)" title="Instruments (software)">Instruments</a></li> <li><a href="/wiki/Apple_Developer_Tools#FileMerge" title="Apple Developer Tools">FileMerge</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Former tools</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Interface_Builder" title="Interface Builder">Interface Builder</a></li> <li><a href="/wiki/Dashcode" title="Dashcode">Dashcode</a></li> <li><a href="/wiki/Quartz_Composer" title="Quartz Composer">Quartz Composer</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Former Applications</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Dashboard_(macOS)" title="Dashboard (macOS)">Dashboard</a></li> <li><a href="/wiki/Front_Row_(software)" title="Front Row (software)">Front Row</a></li> <li><a href="/wiki/IChat" title="IChat">iChat</a></li> <li><a href="/wiki/IPhoto" title="IPhoto">iPhoto</a></li> <li><a href="/wiki/ISync" title="ISync">iSync</a></li> <li><a href="/wiki/ITunes" title="ITunes">iTunes</a> <ul><li><a href="/wiki/History_of_iTunes" title="History of iTunes">history</a></li></ul></li> <li><a href="/wiki/Sherlock_(software)" title="Sherlock (software)">Sherlock</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Utilities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Activity_Monitor_(macOS)" class="mw-redirect" title="Activity Monitor (macOS)">Activity Monitor</a></li> <li><a href="/wiki/AirPort_Utility" class="mw-redirect" title="AirPort Utility">AirPort Utility</a></li> <li><a href="/wiki/Archive_Utility" class="mw-redirect" title="Archive Utility">Archive Utility</a></li> <li><a href="/wiki/Audio_MIDI_Setup" class="mw-redirect" title="Audio MIDI Setup">Audio MIDI Setup</a></li> <li><a href="/wiki/Bluetooth_File_Exchange" class="mw-redirect" title="Bluetooth File Exchange">Bluetooth File Exchange</a></li> <li><a href="/wiki/Boot_Camp_(software)" title="Boot Camp (software)">Boot Camp</a></li> <li><a href="/wiki/ColorSync" title="ColorSync">ColorSync</a></li> <li><a href="/wiki/Apple_Configurator" title="Apple Configurator">Configurator</a></li> <li><a href="/wiki/List_of_built-in_macOS_apps#Console" title="List of built-in macOS apps">Console</a></li> <li><a href="/wiki/List_of_built-in_macOS_apps#Crash_Reporter" title="List of built-in macOS apps">Crash Reporter</a></li> <li><a href="/wiki/Digital_Color_Meter" class="mw-redirect" title="Digital Color Meter">Digital Color Meter</a></li> <li><a href="/wiki/Directory_Utility" class="mw-redirect" title="Directory Utility">Directory Utility</a></li> <li><a href="/wiki/DiskImageMounter" class="mw-redirect" title="DiskImageMounter">DiskImageMounter</a></li> <li><a href="/wiki/Disk_Utility" title="Disk Utility">Disk Utility</a></li> <li><a href="/wiki/Font_Book" title="Font Book">Font Book</a></li> <li><a href="/wiki/Apple_Help_Viewer" class="mw-redirect" title="Apple Help Viewer">Help Viewer</a></li> <li><a href="/wiki/Image_Capture" class="mw-redirect" title="Image Capture">Image Capture</a></li> <li><a href="/wiki/Installer_(macOS)" class="mw-redirect" title="Installer (macOS)">Installer</a></li> <li><a href="/wiki/Keychain_(software)" title="Keychain (software)">Keychain Access</a></li> <li><a href="/wiki/Migration_Assistant_(Apple)" class="mw-redirect" title="Migration Assistant (Apple)">Migration Assistant</a></li> <li><a href="/wiki/Script_Editor" class="mw-redirect" title="Script Editor">Script Editor</a></li> <li><a href="/wiki/System_Settings" title="System Settings">System Settings</a></li> <li><a href="/wiki/System_Information_(Mac)" class="mw-redirect" title="System Information (Mac)">System Information</a></li> <li><a href="/wiki/Terminal_(macOS)" title="Terminal (macOS)">Terminal</a></li> <li><a href="/wiki/Universal_Access" class="mw-redirect" title="Universal Access">Universal Access</a></li> <li><a href="/wiki/VoiceOver" title="VoiceOver">VoiceOver</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Discontinued</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Grab_(macOS)" class="mw-redirect" title="Grab (macOS)">Grab</a></li> <li><a href="/wiki/Network_Utility" class="mw-redirect" title="Network Utility">Network Utility</a></li> <li><a href="/wiki/ODBC_Administrator" class="mw-redirect" title="ODBC Administrator">ODBC Administrator</a></li> <li><a href="/wiki/Remote_Install_Mac_OS_X" class="mw-redirect" title="Remote Install Mac OS X">Remote Install Mac OS X</a></li> <li><a href="/wiki/Apple_Software_Update" class="mw-redirect" title="Apple Software Update">Software Update</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Technologies &<br /><a href="/wiki/User_Interface" class="mw-redirect" title="User Interface">User Interface</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AirDrop" title="AirDrop">AirDrop</a></li> <li><a href="/wiki/AppKit" title="AppKit">AppKit</a></li> <li><a href="/wiki/Apple_File_System" title="Apple File System">Apple File System</a></li> <li><a href="/wiki/Apple_menu" title="Apple menu">Apple menu</a></li> <li><a href="/wiki/Apple_Push_Notification_service" title="Apple Push Notification service">Apple Push Notification service</a></li> <li><a href="/wiki/AppleScript" title="AppleScript">AppleScript</a></li> <li><a href="/wiki/Aqua_(user_interface)" title="Aqua (user interface)">Aqua</a></li> <li><a href="/wiki/Audio_Units" title="Audio Units">Audio Units</a></li> <li><a href="/wiki/AVFoundation" title="AVFoundation">AVFoundation</a></li> <li><a href="/wiki/Bonjour_(software)" title="Bonjour (software)">Bonjour</a></li> <li><a href="/wiki/Bundle_(macOS)" title="Bundle (macOS)">Bundle</a></li> <li><a href="/wiki/CloudKit" title="CloudKit">CloudKit</a></li> <li><a href="/wiki/Cocoa_(API)" title="Cocoa (API)">Cocoa</a></li> <li><a href="/wiki/ColorSync" title="ColorSync">ColorSync</a></li> <li><a href="/wiki/Command_key" title="Command key">Command key</a></li> <li><a href="/wiki/Core_Animation" title="Core Animation">Core Animation</a></li> <li><a href="/wiki/Core_Audio" title="Core Audio">Core Audio</a></li> <li><a href="/wiki/Core_Data" title="Core Data">Core Data</a></li> <li><a href="/wiki/Core_Foundation" title="Core Foundation">Core Foundation</a></li> <li><a href="/wiki/Core_Image" title="Core Image">Core Image</a></li> <li><a href="/wiki/Core_OpenGL" title="Core OpenGL">Core OpenGL</a></li> <li><a href="/wiki/Core_Text" title="Core Text">Core Text</a></li> <li><a href="/wiki/Core_Video" title="Core Video">Core Video</a></li> <li><a href="/wiki/Common_Unix_Printing_System" class="mw-redirect" title="Common Unix Printing System">CUPS</a></li> <li><a href="/wiki/Cover_Flow" title="Cover Flow">Cover Flow</a></li> <li><a href="/wiki/Darwin_(operating_system)" title="Darwin (operating system)">Darwin</a></li> <li><a href="/wiki/Dock_(macOS)" title="Dock (macOS)">Dock</a></li> <li><a href="/wiki/FileVault" title="FileVault">FileVault</a></li> <li><a href="/wiki/List_of_typefaces_included_with_macOS" title="List of typefaces included with macOS">Fonts</a></li> <li><a href="/wiki/Foundation_Kit" title="Foundation Kit">Foundation</a></li> <li><a href="/wiki/Gatekeeper_(macOS)" title="Gatekeeper (macOS)">Gatekeeper</a></li> <li><a href="/wiki/Grand_Central_Dispatch" title="Grand Central Dispatch">Grand Central Dispatch</a></li> <li><a href="/wiki/Apple_Icon_Image_format" title="Apple Icon Image format">icns</a></li> <li><a href="/wiki/ICloud" title="ICloud">iCloud</a></li> <li><a href="/wiki/Kernel_panic#macOS" title="Kernel panic">Kernel panic</a></li> <li><a href="/wiki/Keychain_(software)" title="Keychain (software)">Keychain</a></li> <li><a href="/wiki/Launchd" title="Launchd">launchd</a></li> <li><a href="/wiki/Mach-O" title="Mach-O">Mach-O</a></li> <li><a href="/wiki/Menu_extra" title="Menu extra">Menu extra</a></li> <li><a href="/wiki/Metal_(API)" title="Metal (API)">Metal</a></li> <li><a href="/wiki/Mission_Control_(macOS)" title="Mission Control (macOS)">Mission Control</a></li> <li><a href="/wiki/Night_Shift_(software)" title="Night Shift (software)">Night Shift</a></li> <li><a href="/wiki/OpenCL" title="OpenCL">OpenCL</a></li> <li><a href="/wiki/Option_key" title="Option key">Option key</a></li> <li><a href="/wiki/Preference_Pane" class="mw-redirect" title="Preference Pane">Preference Pane</a></li> <li><a href="/wiki/Property_list" title="Property list">Property list</a></li> <li><a href="/wiki/Quartz_(graphics_layer)" title="Quartz (graphics layer)">Quartz</a></li> <li><a href="/wiki/Quick_Look" title="Quick Look">Quick Look</a></li> <li><a href="/wiki/Rosetta_(software)" title="Rosetta (software)">Rosetta</a></li> <li><a href="/wiki/Virtual_folder#macOS" title="Virtual folder">Smart Folders</a></li> <li><a href="/wiki/Speakable_items" title="Speakable items">Speakable items</a></li> <li><a href="/wiki/Spotlight_(Apple)" title="Spotlight (Apple)">Spotlight</a></li> <li><a href="/wiki/Stacks_(Mac_OS)" title="Stacks (Mac OS)">Stacks</a></li> <li><a href="/wiki/System_Integrity_Protection" title="System Integrity Protection">System Integrity Protection</a></li> <li><a href="/wiki/Uniform_Type_Identifier" title="Uniform Type Identifier">Uniform Type Identifier</a></li> <li><a href="/wiki/Universal_binary" title="Universal binary">Universal binary</a></li> <li><a href="/wiki/WebKit" title="WebKit">WebKit</a></li> <li><a class="mw-selflink selflink">XNU</a></li> <li><a href="/wiki/XQuartz" title="XQuartz">XQuartz</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Deprecated</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/HFS%2B" class="mw-redirect" title="HFS+">HFS+</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Discontinued</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Apple_Type_Services_for_Unicode_Imaging" title="Apple Type Services for Unicode Imaging">ATSUI</a></li> <li><a href="/wiki/BootX_(Apple)" title="BootX (Apple)">BootX</a></li> <li><a href="/wiki/Brushed_metal_(interface)" class="mw-redirect" title="Brushed metal (interface)">Brushed metal</a></li> <li><a href="/wiki/Carbon_(API)" title="Carbon (API)">Carbon</a></li> <li><a href="/wiki/Classic_Environment" class="mw-redirect" title="Classic Environment">Classic Environment</a></li> <li><a href="/wiki/Inkwell_(Macintosh)" title="Inkwell (Macintosh)">Inkwell</a></li> <li><a href="/wiki/QuickTime" title="QuickTime">QuickTime</a></li> <li><a href="/wiki/Spaces_(software)" title="Spaces (software)">Spaces</a></li> <li><a href="/wiki/Xgrid" title="Xgrid">Xgrid</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><i>Italics</i> denote upcoming products.</li> <li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:MacOS" title="Category:MacOS">Category</a></li></ul> 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