View source for Microsoft Windows

{{Short description|Computer operating systems}}
{{Redirect|Windows|the part of a building|Window|other uses}}
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{{Pp-vandalism|small=yes}}
{{More citations needed|date=December 2024}}
{{Use mdy dates|date=February 2022|cs1-dates=l}}
{{Infobox OS
| name = Windows
| logo = Windows logo and wordmark - 2021.svg
| screenshot = Windows 11 Desktop.png
| caption = [[Windows 11]], the latest release of Windows
| developer = [[Microsoft]]
| released = {{Start date and age|1985|11|20}}
| language = 110 languages
| package manager = [[Windows Installer]] (.msi, .msp),<ref>{{Cite web |last1=Su |first1=Christy |last2=Xu |first2=Simonx |date=2021-11-25 |title=FAQ about the Windows Installer .msp files - Dynamics GP |url=https://learn.microsoft.com/en-us/troubleshoot/dynamics/gp/faq-the-windows-installer-dot-msp-files |access-date=2023-09-13 |website=Microsoft Learn |language=en-us |archive-date=July 8, 2023 |archive-url=https://web.archive.org/web/20230708080729/https://learn.microsoft.com/en-us/troubleshoot/dynamics/gp/faq-the-windows-installer-dot-msp-files |url-status=live }}</ref> [[App Installer]] (.msix,.<ref>{{Cite web |last1=dianmsft |last2=Jenks |first2=Alma |last3=Coulter |first3=David |last4=Schofield |first4=McLean |last5=Vintzel |first5=John |last6=Satran |first6=Michael |last7=Donthini |first7=Chaitanya |last8=Kinsman |first8=Mike |date=December 30, 2021 |title=What is MSIX? |url=https://learn.microsoft.com/en-us/windows/msix/overview |access-date=2023-09-13 |website=Microsoft Learn |language=en-us |archive-date=September 25, 2023 |archive-url=https://web.archive.org/web/20230925104716/https://learn.microsoft.com/en-us/windows/msix/overview |url-status=live }}</ref> msixbundle<ref>{{Cite web |last1=Jahiu |first1=Dhurata |last2=Jenks |first2=Alma |last3=v-chmccl |last4=Power |first4=Cory |last5=Coulter |first5=David |last6=Schofield |first6=McLean |last7=Donthini |first7=Chaitanya |last8=Satran |first8=Michael |date=April 13, 2022 |title=How to bundle MSIX packages |url=https://learn.microsoft.com/en-us/windows/msix/packaging-tool/bundle-msix-packages |access-date=2023-09-13 |website=Microsoft Learn |language=en-us |archive-date=October 4, 2023 |archive-url=https://web.archive.org/web/20231004072503/https://learn.microsoft.com/en-us/windows/msix/packaging-tool/bundle-msix-packages |url-status=live }}</ref><ref>{{Cite web |last=Vera |orig-date=April 14, 2023 |date=June 26, 2023 |title=How to Install MSIXBundle on Windows 10/11? 2 Ways to Try! |url=https://www.minitool.com/news/install-msixbundle-windows.html |access-date=2023-09-13 |website=MiniTool |language=en-US |archive-date=August 21, 2023 |archive-url=https://web.archive.org/web/20230821073637/https://www.minitool.com/news/install-msixbundle-windows.html |url-status=live }}</ref>), [[Microsoft Store]] ([[APPX|.appx]], .appxbundle),<ref>{{Cite web |orig-date=October 6, 2015 |date=October 19, 2021 |title=App packages and deployment (Windows Store apps) (Windows) |url=https://learn.microsoft.com/en-us/previous-versions/windows/apps/hh464929(v=win.10)?redirectedfrom=MSDN |url-status=live |archive-url=https://web.archive.org/web/20140330050737/http://msdn.microsoft.com/en-us/library/windows/apps/hh464929.aspx |archive-date=March 30, 2014 |access-date=April 5, 2014 |website=Microsoft Learn}}</ref> [[Windows Package Manager]]
| ui = [[Windows shell]]
| license = [[Proprietary software|Proprietary]] [[commercial software]]
| website = {{Official URL}}
| source_model = {{ubl
| [[Proprietary software|Closed-source]]
| [[Source-available software|Source-available]] (through [[Shared Source Initiative]])
}}
| latest release version = {{Latest stable software release/Windows 11}}
| latest preview version = {{Latest preview software release/Windows 11}}
| marketing_target = Personal computing
| kernel_type = {{plainlist|
* [[Windows NT]] family: [[Hybrid kernel|Hybrid]]
* [[Windows Embedded Compact]]/Windows CE: Hybrid or Monolithic
* [[Windows 9x]] and earlier: [[Monolithic kernel|Monolithic]] ([[MS-DOS]] and [[VMM32]])
}}
| supported_platforms = [[IA-32]], [[x86-64]], [[ARM architecture family|ARM]], [[ARM64]]<br />
Previously: [[x86|16-bit x86]], [[DEC Alpha]], [[MIPS architecture|MIPS]], [[PowerPC]], [[Itanium]]
| updatemodel = {{unbulleted list|[[Windows Update]]|[[Microsoft Store]]|[[Windows Server Update Services]] (WSUS)}}
}}
'''Windows''' is a [[Product lining|product line]] of [[Proprietary software|proprietary]] [[graphical user interface|graphical]] [[operating system]]s developed and marketed by [[Microsoft]]. It is grouped into families and subfamilies that cater to particular sectors of the computing industry – Windows (unqualified) for a consumer or corporate [[workstation]], [[Windows Server]] for a [[Server (computing)|server]] and [[Windows IoT]] for an [[embedded system]]. Windows is sold as either a consumer [[retail]] product or licensed to [[Original equipment manufacturer|third-party hardware manufacturers]] who sell products [[Software bundles|bundled]] with Windows.{{citation needed|date=December 2024}}

The first version of Windows, [[Windows 1.0]], was released on November 20, 1985, as a graphical [[operating system shell]] for [[MS-DOS]] in response to the growing interest in [[graphical user interface]]s (GUIs).<ref>{{Cite web |last=Bellis |first=Mary |date=October 4, 2019 |title=The Unusual History of Microsoft Windows |url=https://www.thoughtco.com/unusual-history-of-microsoft-windows-1992140 |url-status=live |archive-url=https://web.archive.org/web/20200314052249/http://inventors.about.com/od/mstartinventions/a/Windows.htm?rd=1 |archive-date=March 14, 2020 |access-date=January 13, 2023}}</ref> The name "Windows" is a reference to the [[windowing system]] in GUIs.<ref name=":1" /> The 1990 release of [[Windows 3.0]] catapulted its market success and led to various other product families, including the now-defunct [[Windows 9x]], [[Windows Mobile]], [[Windows Phone]], and [[Windows Embedded Compact|Windows CE/Embedded Compact]]. Windows is the [[usage share of operating systems|most popular desktop operating system]] in the world, with a 70% [[market share]] {{as of|2023|March|lc=y}}, according to [[StatCounter]];<ref name="pc">{{Cite web |title=Desktop Operating System Market Share Worldwide |url=https://gs.statcounter.com/os-market-share/desktop/worldwide/#monthly-202208-202306 |access-date=2023-07-16 |website=StatCounter Global Stats |language=en |archive-date=January 27, 2020 |archive-url=https://archive.today/20200127171354/https://gs.statcounter.com/os-market-share/desktop/worldwide/#monthly-202208-202306 |url-status=live }}</ref> however when including [[mobile operating system]]s, it is in second place, behind [[Android (operating system)|Android]].<ref>{{Cite web |last=Keizer |first=Gregg |date=July 14, 2014 |title=Microsoft gets real, admits its device share is just 14% |url=https://www.computerworld.com/article/2490008/microsoft-gets-real--admits-its-device-share-is-just-14-.html |url-status=live |archive-url=https://web.archive.org/web/20160821210826/http://www.computerworld.com/article/2490008/microsoft-windows/microsoft-gets-real--admits-its-device-share-is-just-14-.html |archive-date=August 21, 2016 |website=[[Computerworld]] |publisher=[[IDG]] |quote=<nowiki>[</nowiki>Microsoft's chief operating officer<nowiki>]</nowiki> Turner's 14% came from a new forecast released last week by Gartner, which estimated Windows' share of the shipped device market last year was 14%, and would decrease slightly to 13.7% in 2014. Android will dominate, Gartner said, with a 48% share this year}}</ref>

The most recent version of Windows is [[Windows 11]] for consumer [[personal computer|PCs]] and [[tablet computer|tablets]], [[Windows 11 Enterprise]] for corporations, and [[Windows Server 2025]] for servers. Still supported are some editions of [[Windows 10]], [[Windows Server 2016]] or later (and exceptionally with paid support down to [[Windows Server 2008]]<!-- "Grandfathered Premium Assurance security update support until January 13, 2026"-->).<ref name=PA3>{{cite web|url=https://www.licensingschool.co.uk/wp-content/uploads/2016/04/SQL_Server_and_Windows_Server_Premium_Assurance_Datasheet-December-2016.pdf|title=Windows Server Premium Assurance SQL Server Premium Assurance|website=Licensing School|access-date=April 27, 2025}}</ref><ref name=PA2>{{cite web|url=https://rcpmag.com/Articles/2018/07/13/Microsoft-Replacing-Premiere-Assurance.aspx|title=Microsoft Replacing 'Premiere Assurance' Support with New Security Plan|last=Mackie|first=Kurt|website=Redmond Channel Partner|publisher=1105 Media|date=July 13, 2018|access-date=April 27, 2025}}</ref> As of July 2025, Windows 11 is the most commonly installed desktop version of Windows, with a market share of 52.0%.<ref>{{Cite web |title=Desktop Windows Version Market Share Worldwide |url=https://gs.statcounter.com/windows-version-market-share/desktop/worldwide/#monthly-202406-202507 |access-date=2025-07-07 |website=StatCounter Global Stats |language=en}}</ref> <!-- Do not fracture and overdo the intro into 4 or more paragraphs; keep it simple and concise.-->

==Product line==
{{more citations needed section|date=December 2024}}
{{as of|2025|post=,}} the only active top-level family is [[Windows NT]].{{citation needed|date=December 2024}} The first version, [[Windows NT 3.1]], was intended for [[Server (computing)|server computing]] and corporate [[workstations]]. It grew into a product line of its own and now consists of four sub-families that tend to be released almost simultaneously and share the same kernel.

* Windows (unqualified): For a consumer or corporate [[workstation]] or [[tablet computer|tablet]]. The latest version is [[Windows 11]].{{citation needed|date=December 2024}} Its main competitors are [[macOS]] by [[Apple Inc.|Apple]] and [[Linux]] for personal computers and [[iPadOS]] and [[Android (operating system)|Android]] for tablets (cf. {{section link|Usage share of operating systems|Market share by category}}).
**''Of note: "Windows" refers to both the overall product line and this sub-family of it.''
* [[Windows Server]]: For a server computer. The latest version is [[Windows Server 2025]]. Unlike its client sibling, it has adopted a strong naming scheme. The main competitor of this family is [[Linux]]. (cf. {{section link|Usage share of operating systems|Market share by category}})
* [[Windows PE]]: A lightweight version of its Windows sibling, meant to operate as a [[Live OS|live operating system]], used for installing Windows on bare-metal computers (especially on many computers at once), recovery, or troubleshooting purposes. The latest version is Windows PE 10.{{citation needed|date=December 2024}}
* [[Windows IoT]] (previously Windows Embedded): For [[IoT]] and [[Embedded system|embedded]] computers. The latest version is [[Windows IoT#Enterprise|Windows 11 IoT Enterprise]].<ref>{{Cite web |title=RTOS: Embedded Real Time Operating Systems |url=http://www.microsoft.com/windowsembedded/en-us/products-solutions-overview.aspx |url-status=dead |archive-url=https://web.archive.org/web/20141215074031/http://www.microsoft.com/windowsembedded/en-us/products-solutions-overview.aspx |archive-date=December 15, 2014 |access-date=November 7, 2014 |website=microsoft.com |publisher=[[Microsoft]] |df=mdy-all}}</ref> Like Windows Server, the main competitor of this family is Linux. (cf. {{section link|Usage share of operating systems|Market share by category}})

These top-level Windows families are no longer actively developed:

* [[Windows 9x]]: Intended exclusively for the consumer market. The first version was [[Windows 95]], which was followed by [[Windows 98]]. The last version of the Windows 9x family was [[Windows Me]], which was widely regarded as one of the worst operating systems of all time, with ''[[PC World]]'' labeling it as "Mistake Edition" and placing it 4th in their list of ''Worst Tech Products'' in 2006<ref name="WinMEbad" />). All versions of the Windows 9x family have a [[monolithic kernel]] that uses [[MS-DOS]] as a foundation alongside the kernel first used with Windows 95. This line has since been defunct, with Microsoft now catering to the consumer market with Windows NT starting with [[Windows XP]].{{citation needed|date=December 2024}}
* [[Windows Mobile]]: The predecessor to Windows Phone, a mobile phone and [[Personal digital assistant|PDA]] operating system. The first version was called [[Pocket PC 2000]]. The third version, [[Windows Mobile 2003]], was the first version to adopt the Windows Mobile trademark. The last published version was [[Windows Mobile 6.5]].
* [[Windows Phone]]: Sold only to smartphone manufacturers. The first version was [[Windows Phone 7]], followed by [[Windows Phone 8]] and [[Windows Phone 8.1]]. It was succeeded by [[Windows 10 Mobile]], which is also defunct.
*[[Windows Embedded Compact]]: Most commonly known by its former name, Windows CE, it is a [[hybrid kernel]] operating system optimized for low power and memory systems, with [[OEM]]s able to modify the [[user interface|UI]] to suit their needs. The final version was Windows Embedded Compact 2013, and it is succeeded by [[Windows IoT]].{{citation needed|date=December 2024}}

== History ==
{{Main|Microsoft Windows version history}}
{{See also|List of Microsoft Windows versions}}

The term ''Windows'' collectively describes any or all of several generations of [[Microsoft]] [[operating system]] products. These products are generally categorized as follows:

=== Early versions ===
{{Main|Windows 1.0|Windows 2.0|Windows 2.1}}

The history of Windows dates back to 1981 when Microsoft started work on a program called "Interface Manager". The name "Windows" comes from the fact that the system was one of the first to use graphical boxes to represent programs; in the industry, at the time, these were called "windows" and the underlying software was called "windowing software."<ref name=":1">{{Cite web |last=Edwards |first=Benj |date=2022-02-07 |title=Why Is Windows Called Windows? |url=https://www.howtogeek.com/781573/why-is-windows-called-windows/ |access-date=2024-09-03 |website=How-To Geek |language=en}}</ref> It was announced in November 1983 (after the [[Apple Lisa]], but before the [[Macintosh 128K|Macintosh]]) under the name "Windows", but [[Windows 1.0]] was not released until November 1985.<ref>{{Cite web |title=A history of Windows |url=http://windows.microsoft.com/en-in/windows/history#T1=era0 |url-status=dead |archive-url=https://web.archive.org/web/20160611182917/http://windows.microsoft.com/en-in/windows/history#T1=era0 |archive-date=June 11, 2016 |access-date=2023-01-07 |website=Microsoft Windows |language=en-US}}</ref> Windows 1.0 was to compete with [[Apple Inc.|Apple]]'s operating system, but achieved little popularity. Windows 1.0 is not a complete operating system; rather, it extends [[MS-DOS]]. The shell of Windows 1.0 is a program known as the [[MS-DOS Executive]]. Components included [[Windows Calculator|Calculator]], Calendar, [[Cardfile]], [[ClipBook Viewer|Clipboard Viewer]], Clock, [[Control Panel (Windows)|Control Panel]], [[Windows Notepad|Notepad]], [[Microsoft Paint|Paint]], [[Reversi]], [[Terminal emulator|Terminal]] and [[Microsoft Write|Write]]. Windows 1.0 does not allow overlapping windows. Instead, all windows are [[tiling window manager|tiled]]. Only modal dialog boxes may appear over other windows. Microsoft sold as included Windows Development libraries with the C development environment, which included numerous windows samples.<ref>{{Cite book |title=Microsoft C 5.0: C Language Reference Guide |publisher=Microsoft |year=1987 |pages=250–267}}</ref>

[[Windows 2.0]] was released in December 1987, and was more popular than its predecessor. It features several improvements to the user interface and memory management.<ref>{{Cite news |title=A legacy of Windows, part 1: Windows 1-2-3 – TechRepublic |language=en |work=TechRepublic |url=http://www.techrepublic.com/article/a-legacy-of-windows-part-1-windows-1-2-3/ |url-status=live |access-date=March 26, 2017 |archive-url=https://web.archive.org/web/20170327170048/http://www.techrepublic.com/article/a-legacy-of-windows-part-1-windows-1-2-3/ |archive-date=March 27, 2017}}</ref> Windows 2.03 changed the OS from tiled windows to overlapping windows. The result of this change led to [[Apple Computer, Inc. v. Microsoft Corp.|Apple Computer filing a suit against Microsoft]] alleging infringement on Apple's copyrights (eventually settled in court in Microsoft's favor in 1993).<ref>{{Cite web |year=2006 |title=The Apple vs. Microsoft GUI Lawsuit |url=http://lowendmac.com/orchard/06/apple-vs-microsoft.html |url-status=live |archive-url=https://web.archive.org/web/20080304145809/http://lowendmac.com/orchard/06/apple-vs-microsoft.html |archive-date=March 4, 2008 |access-date=March 12, 2008}}</ref><ref>{{Cite web |title=Apple Computer, Inc. v. MicroSoft Corp., 35 F.3d 1435 (9th Cir. 1994) |url=http://home.earthlink.net/~mjohnsen/Technology/Lawsuits/appvsms.html |url-status=dead |archive-url=https://web.archive.org/web/20071214033452/http://home.earthlink.net/~mjohnsen/Technology/Lawsuits/appvsms.html |archive-date=December 14, 2007 |access-date=March 12, 2008}}</ref> Windows 2.0 also introduced more sophisticated [[keyboard shortcut]]s and could make use of [[expanded memory]].

[[Windows 2.1]] was released in two different versions: [[Windows/286]] and [[Windows/386]]. Windows/386 uses the [[virtual 8086 mode]] of the [[Intel 80386]] to multitask several DOS programs and the [[paging|paged memory model]] to emulate expanded memory using available [[extended memory]]. Windows/286, in spite of its name, runs on both [[Intel 8086]] and [[Intel 80286]] processors. It runs in [[real mode]] but can make use of the [[high memory area]].<ref name="infoworld-19880704">{{cite magazine |last1=Patton |first1=Carole |last2=Mace |first2=Scott |title=Windows Gets More Memory With Upgrade |magazine=[[InfoWorld]] |date=4 July 1988 |volume=10 |issue=27 |page=1 |url=https://books.google.com/books?id=4z4EAAAAMBAJ&pg=PA1 |access-date=9 January 2024 |issn=0199-6649 |archive-url=https://web.archive.org/web/20240109100230/https://books.google.com/books?id=4z4EAAAAMBAJ&pg=PA1 |archive-date=9 January 2024 |url-status=live }}</ref>

In addition to full Windows packages, there were runtime-only versions that shipped with early Windows software from third parties and made it possible to run their Windows software on MS-DOS and without the full Windows feature set.

The early versions of Windows are often thought of as graphical shells, mostly because they ran on top of MS-DOS and used it for [[file system]] services.<ref name="Evolution">{{Cite web |title=Windows Evolution |url=http://news.soft32.com/windows-evolution_1629.html |url-status=dead |archive-url=https://web.archive.org/web/20080208174626/http://news.soft32.com/windows-evolution_1629.html |archive-date=February 8, 2008 |publisher=Soft32.com News}}</ref> However, even the earliest Windows versions already assumed many typical operating system functions; notably, having their own [[executable file format]] and providing their own [[device driver]]s (timer, graphics, printer, mouse, keyboard and sound). Unlike MS-DOS, Windows allowed users to execute multiple graphical applications at the same time, through [[Nonpreemptive multitasking|cooperative multitasking]]. Windows implemented an elaborate, segment-based, software virtual memory scheme, which allows it to run applications larger than available memory: code segments and [[resource (Windows)|resources]] are swapped in and thrown away when memory became scarce; data segments moved in memory when a given application had relinquished processor control.

=== Windows 3.x ===
{{Main|Windows 3.0|Windows 3.1}}
[[File:Windows 3.0 workspace.png|thumb|upright=1.15|left|Windows 3.0, released in 1990]]

[[Windows 3.0]], released in 1990, improved the design, mostly because of [[virtual memory]] and loadable virtual device drivers ([[VxD]]s) that allow Windows to share arbitrary devices between multi-tasked DOS applications.{{citation needed|date=September 2023}} Windows 3.0 applications can run in [[protected mode]], which gives them access to several megabytes of memory without the obligation to participate in the software virtual memory scheme. They run inside the same address space, where the segmented memory provides a degree of protection. Windows 3.0 also featured improvements to the user interface. Microsoft rewrote critical operations from [[C (programming language)|C]] into [[Assembly language|assembly]]. Windows 3.0 was the first version of Windows to achieve broad commercial success, selling 2&nbsp;million copies in the first six months.<ref>{{Cite web |title=Chronology of Personal Computer Software |url=http://www.islandnet.com/~kpolsson/compsoft/soft1991.htm |url-status=dead |archive-url=https://web.archive.org/web/20120211132458/http://www.islandnet.com/~kpolsson/compsoft/soft1991.htm |archive-date=February 11, 2012}}</ref><ref>{{Cite web |title=Microsoft Company |url=http://www.thocp.net/companies/microsoft/microsoft_company.htm |url-status=dead |archive-url=https://web.archive.org/web/20080514211138/http://www.thocp.net/companies/microsoft/microsoft_company.htm |archive-date=May 14, 2008}}</ref>
[[File:Microsoft Windows for Workgroups 3.11 mit 9 Setup HD-Disketten.jpg|thumb|Versions before Windows 95 had to be installed from [[floppy disk]]s by end users (or in professional environments with a network installation); here Windows for Workgroups with nine 3.5-inch-disks to be inserted sequentially.]]
Windows 3.1, made [[general availability release|generally available]] on March 1, 1992, featured a facelift. In October 1992, Windows for Workgroups, a special version with integrated [[peer-to-peer networking]] features, was released. It was sold along with Windows 3.1. Support for Windows 3.1 ended on December 31, 2001.<ref>{{Cite web |title=Windows 3.1 Standard Edition Support Lifecycle |url=http://support.microsoft.com/lifecycle/?LN=en-us&p1=3078&x=10&y=11 |url-status=dead |archive-url=https://web.archive.org/web/20120112112159/http://support.microsoft.com/lifecycle/?LN=en-us&p1=3078&x=10&y=11 |archive-date=January 12, 2012 |access-date=January 3, 2011}}</ref>

Windows 3.2, released in 1994, is an updated version of the Chinese version of Windows 3.1.<ref>{{Cite web |title=Microsoft Windows Simplified Chinese 3.2 Upgrade Is Available |url=http://support.microsoft.com/kb/129451 |url-status=dead |archive-url=https://web.archive.org/web/20061108051648/http://support.microsoft.com/kb/129451 |archive-date=November 8, 2006 |website=Microsoft Support |publisher=Microsoft}}</ref> The update was limited to this language version, as it fixed only issues related to the complex writing system of the Chinese language.<ref>{{Cite web |date=October 30, 2003 |title=Microsoft Windows Simplified Chinese 3.2 Upgrade Is Available |url=http://support.microsoft.com/default.aspx?scid=kb;en-us;129451 |url-status=dead |archive-url=https://web.archive.org/web/20110524050602/http://support.microsoft.com/default.aspx?scid=kb;en-us;129451 |archive-date=May 24, 2011 |access-date=September 4, 2009 |publisher=Microsoft}}</ref> Windows 3.2 was generally sold by computer manufacturers with a ten-disk version of [[MS-DOS]] that also had [[Simplified Chinese characters]] in basic output and some translated utilities.{{citation needed|date=December 2024}}

=== Windows 9x ===
{{Main|Windows 9x|Windows 95|Windows 98|Windows Me}}
The next major consumer-oriented release of Windows, [[Windows 95]], was released on August 24, 1995. While still remaining MS-DOS-based, Windows 95 introduced support for native [[32-bit application]]s, [[plug and play]] hardware, [[preemptive multitasking]], [[long file name]]s of up to 255 characters, and provided increased stability over its predecessors. Windows 95 also introduced a redesigned, [[Object-oriented design|object oriented]] user interface, replacing the previous [[Program Manager]] with the [[Start menu]], [[taskbar]], and [[Windows Explorer]] [[Windows shell|shell]]. Windows 95 was a major commercial success for Microsoft; Ina Fried of [[CNET]] remarked that "by the time Windows 95 was finally ushered off the market in 2001, it had become a fixture on computer desktops around the world."<ref>{{Cite news |last=Fried |first=Ina |date=August 25, 2010 |title=Windows 95 turns 15: Has Microsoft's OS peaked? |url=http://www.cnn.com/2010/TECH/web/08/25/cnet.microsoft.windows/index.html |url-status=live |archive-url=https://web.archive.org/web/20100826141242/http://www.cnn.com/2010/TECH/web/08/25/cnet.microsoft.windows/index.html |archive-date=August 26, 2010 |access-date=August 22, 2012 |publisher=CNET/CNN Tech}}</ref> Microsoft published four OEM Service Releases (OSR) of Windows 95, each of which was roughly equivalent to a [[service pack]]. The first OSR of Windows 95 was also the first version of Windows to be bundled with Microsoft's [[web browser]], [[Internet Explorer]].<ref name="apr96ms">{{Cite web |date=April 30, 1996 |title=Microsoft Internet Explorer Web Browser Available on All Major Platforms, Offers Broadest International Support |url=https://news.microsoft.com/1996/04/30/microsoft-internet-explorer-web-browser-available-on-all-major-platforms-offers-broadest-international-support/ |url-status=live |archive-url=https://web.archive.org/web/20080115072757/http://www.microsoft.com/presspass/press/1996/apr96/iemompr.mspx |archive-date=January 15, 2008 |access-date=February 14, 2011 |website=News Center |publisher=Microsoft |location=[[San Jose, California]]}}</ref> Mainstream support for Windows 95 ended on December 31, 2000, and extended support for Windows 95 ended on December 31, 2001.<ref name="Windows 95 Support Lifecycle">{{Cite web |title=Windows 95 Support Lifecycle |url=http://support.microsoft.com/lifecycle/?p1=7864 |url-status=live |archive-url=https://web.archive.org/web/20121122121129/http://support.microsoft.com/lifecycle/?p1=7864 |archive-date=November 22, 2012 |access-date=January 3, 2011 |publisher=Microsoft}}</ref>

Windows 95 was followed up with the release of [[Windows 98]] on June 25, 1998, which introduced the [[Windows Driver Model]], support for [[Universal Serial Bus#Overview|USB composite devices]], support for [[ACPI]], [[hibernation (computing)|hibernation]], and support for [[multi-monitor]] configurations. Windows 98 also included integration with [[Internet Explorer 4]] through [[Active Desktop]] and other aspects of the [[Windows Desktop Update]] (a series of enhancements to the Explorer shell which was also made available for Windows 95). In May 1999, Microsoft released [[Windows 98 Second Edition]], an updated version of Windows 98. Windows 98 SE added [[Internet Explorer 5.0]] and [[Windows Media Player]] 6.2 amongst other upgrades. Mainstream support for Windows 98 ended on June 30, 2002, and extended support for Windows 98 ended on July 11, 2006.<ref name="Windows 98 Standard Edition Support Lifecycle">{{Cite web |title=Windows 98 Standard Edition Support Lifecycle |url=http://support.microsoft.com/lifecycle/?p1=6513 |url-status=live |archive-url=https://web.archive.org/web/20121122120808/http://support.microsoft.com/lifecycle/?p1=6513 |archive-date=November 22, 2012 |access-date=January 3, 2011 |publisher=Microsoft}}</ref>

On September 14, 2000, Microsoft released [[Windows Me]] (Millennium Edition), the last DOS-based version of Windows. Windows Me incorporated visual interface enhancements from its Windows NT-based counterpart [[Windows 2000]], had faster boot times than previous versions (which however, required the removal of the ability to access a [[real mode]] DOS environment, removing compatibility with some older programs),<ref name="FastBoot1">{{Cite web |date=December 4, 2001 |title=Improving "Cold Boot" Time for System Manufacturers |url=http://www.microsoft.com/whdc/archive/fast-boot.mspx |url-status=dead |archive-url=https://web.archive.org/web/20100213120324/http://www.microsoft.com/whdc/archive/fast-boot.mspx |archive-date=February 13, 2010 |access-date=August 26, 2010 |publisher=Microsoft}}</ref> expanded [[multimedia]] functionality (including Windows Media Player 7, [[Windows Movie Maker]], and the [[Windows Image Acquisition]] framework for retrieving images from scanners and digital cameras), additional system utilities such as [[System File Protection]] and [[System Restore]], and updated [[home network]]ing tools.<ref name="pcw-me">{{Cite magazine |title=Windows Millennium Edition: All About Me |url=http://www.pcworld.com/article/17791/article.html |url-status=dead |magazine=PC World |archive-url=https://web.archive.org/web/20130801115257/http://www.pcworld.com/article/17791/article.html |archive-date=August 1, 2013 |access-date=May 21, 2013}}</ref> However, Windows Me was faced with criticism for its speed and instability, along with hardware compatibility issues and its removal of real mode DOS support. ''[[PC World]]'' considered Windows Me to be one of the worst operating systems Microsoft had ever released, and the fourth worst tech product of all time.<ref name="WinMEbad">{{Cite web |date=May 26, 2006 |title=The 25 Worst Tech Products of All Time |url=https://www.pcworld.com/article/535838/worst_products_ever.html |url-status=live |archive-url=https://web.archive.org/web/20230107210308/https://www.pcworld.com/article/535838/worst_products_ever.html |archive-date=January 7, 2023 |access-date=January 7, 2023 |website=[[PC World]] |publisher=[[International Data Group|IDG]]}}</ref>

=== Windows NT ===
{{Main|Windows NT}}

==== Version history ====

===== Early versions (Windows NT 3.1/3.5/3.51/4.0/2000) =====
{{Main|Windows NT 3.1|Windows NT 3.5|Windows NT 3.51 |Windows NT 4.0|Windows 2000}}
[[File:Windows Logo (1992-2001).svg|thumb|Windows logo (1995–2001)]]
In November 1988, a new development team within Microsoft (which included former [[Digital Equipment Corporation]] developers [[Dave Cutler]] and [[Mark Lucovsky]]) began work on a revamped version of [[IBM]] and Microsoft's [[OS/2]] operating system known as "NT OS/2". NT OS/2 was intended to be a secure, [[multi-user]] operating system with [[POSIX]] compatibility and a modular, [[Software portability|portable]] kernel with [[preemptive multitasking]] and support for multiple processor architectures. However, following the successful release of [[Windows 3.0]], the NT development team decided to rework the project to use an extended [[32-bit computing|32-bit]] port of the [[Windows API]] known as Win32 instead of those of OS/2. Win32 maintained a similar structure to the Windows [[API]]s (allowing existing Windows applications to easily be [[Porting|ported]] to the platform), but also supported the capabilities of the existing NT [[Kernel (operating system)|kernel]]. Following its approval by Microsoft's staff, development continued on what was now Windows NT, the first 32-bit version of Windows. However, IBM objected to the changes, and ultimately continued OS/2 development on its own.<ref name="insident">{{Cite book |last=Custer |first=Helen |url=https://archive.org/details/insidewindowsnt00cust |title=Inside Windows NT |publisher=Microsoft Press |year=1993 |isbn=1-55615-481-X |location=Redmond |url-access=registration}}</ref><ref name="thurrott-nt" />

Windows NT was the first Windows operating system based on a [[hybrid kernel]]. The hybrid kernel was designed as a modified [[microkernel]], influenced by the [[Mach (kernel)|Mach microkernel]] developed by [[Richard Rashid]] at Carnegie Mellon University, but without meeting all of the criteria of a pure microkernel.

The first release of the resulting operating system, [[Windows NT 3.1]] (named to associate it with [[Windows 3.1]]) was released in July 1993, with versions for desktop [[workstation]]s and [[server (computing)|servers]]. [[Windows NT 3.5]] was released in September 1994, focusing on performance improvements and support for [[Novell]]'s [[NetWare]], and was followed up by [[Windows NT 3.51]] in May 1995, which included additional improvements and support for the [[PowerPC]] architecture. [[Windows NT 4.0]] was released in June 1996, introducing the redesigned interface of [[Windows 95]] to the NT series. On February 17, 2000, Microsoft released [[Windows 2000]], a successor to NT 4.0. The Windows NT name was dropped at this point in order to put a greater focus on the Windows brand.<ref name="thurrott-nt">{{Cite web |last=Thurrott |first=Paul |date=January 24, 2003 |title=Windows Server 2003: The Road To Gold – Part One: The Early Years |url=http://www.winsupersite.com/reviews/winserver2k3_gold1.asp |archive-url=https://web.archive.org/web/20050101005634/http://www.winsupersite.com/reviews/winserver2k3_gold1.asp |archive-date=January 1, 2005 |access-date=May 28, 2012}}</ref>

===== Windows XP =====
{{Main|Windows XP}}
[[File:Windows logo variant (2003).svg|thumb|A variation of the 2001–2006 Windows logo from 2003 using the [[Segoe]] typeface instead of the [[Franklin Gothic]] typeface. This variation was mainly used for branding purposes.]]
The next major version of Windows NT, [[Windows XP]], was released to manufacturing (RTM) on August 24, 2001, and to the general public on October 25, 2001. The introduction of Windows XP aimed to unify the consumer-oriented [[Windows 9x]] series with the architecture introduced by Windows NT, a change which Microsoft promised would provide better performance over its DOS-based predecessors. Windows XP would also introduce a redesigned user interface (including an updated Start menu and a "task-oriented" [[File Explorer|Windows Explorer]]), streamlined multimedia and networking features, [[Internet Explorer 6]], integration with Microsoft's [[Microsoft account|.NET Passport]] services, a "[[Windows XP#Backwards compatibility|compatibility mode]]" to help provide [[backwards compatibility]] with software designed for previous versions of Windows, and [[Windows Remote Assistance|Remote Assistance]] functionality.<ref name="cnet-xpreview">{{Cite web |title=Windows XP review |url=http://reviews.cnet.com/windows/microsoft-windows-xp-home/4505-3672_7-6534881.html |url-status=dead |archive-url=https://web.archive.org/web/20130526024030/http://reviews.cnet.com/windows/microsoft-windows-xp-home/4505-3672_7-6534881.html |archive-date=May 26, 2013 |access-date=May 24, 2013 |website=CNET}}</ref><ref>{{Cite web |date=March 12, 2002 |title=Windows XP Program Compatibility Wizard |url=https://www.serverwatch.com/guides/windows-xp-program-compatibility-wizard/ |url-status=live |archive-url=https://web.archive.org/web/20211113012030/https://www.serverwatch.com/guides/windows-xp-program-compatibility-wizard/ |archive-date=November 13, 2021 |access-date=November 13, 2021 |website=ServerWatch}}</ref>

At retail, Windows XP was marketed in two main [[Stock keeping unit|editions]]: the "Home" edition was targeted towards consumers, while the "Professional" edition was targeted towards business environments and [[power user]]s, and included additional security and networking features. Home and Professional were later accompanied by the "[[Windows Media Center|Media Center]]" edition (designed for [[home theater PC]]s, with an emphasis on support for [[DVD]] playback, [[TV tuner card]]s, [[Digital video recorder|DVR]] functionality, and remote controls), and the "Tablet PC" edition (designed for mobile devices meeting its [[Microsoft Tablet PC|specifications]] for a [[tablet computer]], with support for [[stylus]] pen input and additional pen-enabled applications).<ref>{{Cite news |last=David Coursey |date=October 25, 2001 |title=The 10 top things you MUST know about Win XP |work=[[ZDNet]] |url=http://review.zdnet.com/4520-6033_16-4206552.html |url-status=dead |access-date=July 22, 2008 |archive-url=http://webarchive.loc.gov/all/20090403131228/http://review.zdnet.com/4520-6033_16-4206552.html |archive-date=April 3, 2009}}</ref><ref>{{Cite web |last=David Coursey |date=August 31, 2001 |title=Your top Windows XP questions answered! (Part One) |url=http://review.zdnet.com/4520-6033_16-4206367.html |archive-url=https://web.archive.org/web/20071219121319/http://review.zdnet.com/4520-6033_16-4206367.html |archive-date=December 19, 2007 |access-date=January 3, 2011 |website=[[ZDNet]] |publisher=[[CBS Interactive|CNET Networks]]}}</ref><ref>{{Cite web |date=September 3, 2002 |title=A Look at Freestyle and Mira |url=http://www.winsupersite.com/article/showcase/a-look-at-freestyle-and-mira.aspx |access-date=January 3, 2011 |website=Paul Thurrott's SuperSite for Windows |publisher=Penton}}{{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Mainstream support for Windows XP ended on April 14, 2009. Extended support ended on April 8, 2014.<ref>{{Cite web |title=Windows XP Professional Lifecycle Support |url=http://support.microsoft.com/lifecycle/?p1=3223 |url-status=live |archive-url=https://web.archive.org/web/20130227071350/http://support.microsoft.com/lifecycle/?p1=3223 |archive-date=February 27, 2013 |access-date=January 3, 2011}}</ref>

After Windows 2000, Microsoft also changed its release schedules for server operating systems; the server counterpart of Windows XP, [[Windows Server 2003]], was released in April 2003.<ref name="thurrott-nt" /> It was followed in December 2005, by Windows Server 2003 R2.

===== Windows Vista =====
{{Main|Windows Vista}}

After a lengthy [[development of Windows Vista|development process]], [[Windows Vista]] was released on November 30, 2006, for volume licensing and January 30, 2007, for consumers. It contained a number of [[Features new to Windows Vista|new features]], from a redesigned shell and user interface to significant [[Technical features new to Windows Vista|technical changes]], with a particular focus on [[Security and safety features new to Windows Vista|security features]]. It was available in a number of [[Windows Vista editions|different editions]], and has been subject to [[Criticism of Windows Vista|some criticism]], such as drop of performance, longer boot time, criticism of new UAC, and stricter license agreement. Vista's server counterpart, [[Windows Server 2008]] was released in early 2008.

===== Windows 7 =====
{{Main|Windows 7}}
On July 22, 2009, [[Windows 7]] and [[Windows Server 2008 R2]] were released to manufacturing (RTM) and released to the public three months later on October 22, 2009. Unlike its predecessor, Windows Vista, which introduced a large number of new features, Windows 7 was intended to be a more focused, incremental upgrade to the Windows line, with the goal of being compatible with applications and hardware with which Windows Vista was already compatible.<ref>{{Cite web |last=Nash |first=Mike |date=October 28, 2008 |title=Windows 7 Unveiled Today at PDC 2008 |url=https://blogs.windows.com/windowsexperience/2008/10/28/windows-7-unveiled-today-at-pdc-2008/ |url-status=live |archive-url=https://web.archive.org/web/20081101011844/http://windowsteamblog.com/blogs/windows7/archive/2008/10/28/windows-7-unveiled-today-at-pdc-2008.aspx |archive-date=November 1, 2008 |access-date=November 11, 2008 |website=Windows Experience Blog |publisher=Microsoft}}</ref> Windows 7 has [[multi-touch]] support, a redesigned [[Windows shell]] with an updated [[taskbar]] with revealable [[Features new to Windows 7#Jump lists|jump lists]] that contain shortcuts to files frequently used with specific applications and shortcuts to tasks within the application,<ref>{{Cite web |last1=Kiriaty |first1=Yochay |last2=Goldshtein |first2=Sasha |date=2009 |title=Windows 7 Taskbar APIs |url=https://docs.microsoft.com/en-us/archive/msdn-magazine/2009/brownfield/windows-7-taskbar-apis |url-status=live |archive-url=https://web.archive.org/web/20210821123232/https://docs.microsoft.com/en-us/archive/msdn-magazine/2009/brownfield/windows-7-taskbar-apis |archive-date=August 21, 2021 |access-date=August 21, 2021 |website=docs.microsoft.com |language=en-us}}</ref> a home networking system called [[Features new to Windows 7#HomeGroup|HomeGroup]],<ref>{{Cite web |last=LeBlanc |first=Brandon |date=October 28, 2008 |title=How Libraries & HomeGroup Work Together in Windows 7 |url=https://blogs.windows.com/windowsexperience/2008/10/28/how-libraries-homegroup-work-together-in-windows-7/ |url-status=live |archive-url=https://web.archive.org/web/20081102042853/http://windowsteamblog.com/blogs/windowsexperience/archive/2008/10/28/how-libraries-amp-homegroup-work-together-in-windows-7.aspx |archive-date=November 2, 2008 |access-date=November 11, 2008 |website=Windows Experience Blog |publisher=Microsoft}}</ref> and performance improvements.
<!--{{anchor|Multilingual support: IMEs and LIPs}}-->

===== Windows 8 and 8.1 =====
{{Main|Windows 8|Windows 8.1}}
[[File:Windows logo and wordmark - 2012-2015.svg|thumb|Windows logo (2012–2015)]]
[[Windows 8]], the successor to Windows 7, was released generally on October 26, 2012. A number of significant changes were made on Windows 8, including the introduction of a user interface based around Microsoft's [[Metro (design language)|Metro design language]] with optimizations for [[multi-touch|touch-based]] devices such as [[tablet computer|tablets]] and all-in-one PCs. These changes include the [[Start menu#Third version|Start screen]], which uses large tiles that are more convenient for touch interactions and allow for the display of continually updated information, and a new class of [[application software|apps]] which are designed primarily for use on touch-based devices. The new Windows version required a minimum resolution of 1024×768 pixels,<ref name="zdnet-smallertab">{{Cite web |title=New Windows 8 hardware specs hint at 7-inch tablets and a Microsoft Reader |url=https://www.zdnet.com/article/new-windows-8-hardware-specs-hint-at-7-inch-tablets-and-a-microsoft-reader/ |url-status=live |archive-url=https://web.archive.org/web/20141204160922/http://www.zdnet.com/new-windows-8-hardware-specs-hint-at-7-inch-tablets-and-a-microsoft-reader-7000013271/ |archive-date=December 4, 2014 |access-date=March 29, 2013 |publisher=ZDNet}}</ref> effectively making it unfit for [[netbook]]s with 800×600-pixel screens.

Other changes include increased integration with [[cloud computing|cloud services]] and other online platforms (such as [[social networking service|social networks]] and Microsoft's own [[OneDrive]] (formerly SkyDrive) and [[Xbox Live]] services), the [[Windows Store]] service for software distribution, and a new variant known as [[Windows RT]] for use on devices that utilize the [[ARM architecture family|ARM architecture]], and a new keyboard shortcut for [[screenshot]]s.<ref>{{Cite web |last=Paul |first=Ian |date=July 5, 2021 |title=How to Take Screenshots in Windows 10, 8, and 7 |url=https://www.lifewire.com/take-screenshot-windows-7-8-10-4049964 |url-status=live |archive-url=https://web.archive.org/web/20220319081530/https://www.lifewire.com/take-screenshot-windows-7-8-10-4049964 |archive-date=March 19, 2022 |access-date=August 11, 2021}}</ref><ref name="pcw-testdrivertm">{{Cite web |last=Case |first=Loyd |title=Test Driving Windows 8 RTM |url=https://www.pcworld.com/article/460667/windows_8_install_and_test_drive_welcome_to_microsofts_brave_new_world.html |url-status=live |archive-url=https://web.archive.org/web/20230107205229/https://www.pcworld.com/article/460667/windows_8_install_and_test_drive_welcome_to_microsofts_brave_new_world.html |archive-date=January 7, 2023 |access-date=January 7, 2023 |website=PC World |publisher=IDG}}</ref><ref name="bi-windows8">{{Cite web |last=Rosoff |first=Matt |title=Here's Everything You Wanted To Know About Microsoft's Upcoming iPad Killers |url=http://articles.businessinsider.com/2012-02-09/tech/31040510_1_steven-sinofsky-pcs-microsoft-first |url-status=dead |archive-url=https://web.archive.org/web/20130122030754/http://articles.businessinsider.com/2012-02-09/tech/31040510_1_steven-sinofsky-pcs-microsoft-first |archive-date=January 22, 2013 |access-date=February 10, 2012 |website=[[Business Insider]]}}</ref><ref name="bw-win8editions">{{Cite web |date=April 16, 2012 |title=Announcing the Windows 8 Editions |url=http://windowsteamblog.com/windows/b/bloggingwindows/archive/2012/04/16/announcing-the-windows-8-editions.aspx |url-status=dead |archive-url=https://web.archive.org/web/20120418070243/http://windowsteamblog.com/windows/b/bloggingwindows/archive/2012/04/16/announcing-the-windows-8-editions.aspx |archive-date=April 18, 2012 |access-date=April 17, 2012 |publisher=Microsoft}}</ref><ref name="bw8-buildingarm">{{Cite web |title=Building Windows for the ARM processor architecture |url=http://blogs.msdn.com/b/b8/archive/2012/02/09/building-windows-for-the-arm-processor-architecture.aspx |url-status=dead |archive-url=https://web.archive.org/web/20121126020149/http://blogs.msdn.com/b/b8/archive/2012/02/09/building-windows-for-the-arm-processor-architecture.aspx |archive-date=November 26, 2012 |access-date=November 21, 2012 |publisher=Microsoft}}</ref><ref name="verge-talkswin8">{{Cite web |date=May 17, 2012 |title=Microsoft talks Windows Store features, Metro app sandboxing for Windows 8 developers |url=https://www.theverge.com/2012/5/17/3026590/microsoft-windows-8-developers-windows-store-sandboxing |url-status=live |archive-url=https://web.archive.org/web/20120910150803/http://www.theverge.com/2012/5/17/3026590/microsoft-windows-8-developers-windows-store-sandboxing |archive-date=September 10, 2012 |access-date=September 8, 2012 |website=[[The Verge]] |publisher=[[Vox Media]]}}</ref><ref name="pcw-building">{{Cite news |last=Miller |first=Michael |title=Build: More Details On Building Windows 8 Metro Apps |work=PC Magazine |url=http://forwardthinking.pcmag.com/show-reports/287736-build-more-details-on-building-windows-8-metro-apps |url-status=dead |access-date=February 10, 2012 |archive-url=https://web.archive.org/web/20120217202913/http://forwardthinking.pcmag.com/show-reports/287736-build-more-details-on-building-windows-8-metro-apps |archive-date=February 17, 2012}}</ref> An update to Windows 8, called [[Windows 8.1]],<ref>{{Cite web |title=Windows 8.1 now available! |url=http://blogs.windows.com/windows/b/bloggingwindows/archive/2013/10/17/windows-8-1-now-available.aspx |url-status=dead |archive-url=https://web.archive.org/web/20131019035341/http://blogs.windows.com/windows/b/bloggingwindows/archive/2013/10/17/windows-8-1-now-available.aspx |archive-date=October 19, 2013 |access-date=October 31, 2013 |website=blogs.windows.com}}</ref> was released on October 17, 2013, and includes features such as new live tile sizes, deeper [[OneDrive]] integration, and many other revisions. [[Windows 8]] and [[Windows 8.1]] have been subject to some criticism, such as the removal of the [[Start menu]].

===== Windows 10 =====
{{Main|Windows 10}}
[[File:Windows wordmark darkblue 2015.svg|thumb|Windows logo (2015–2021)]]
On September 30, 2014, Microsoft announced [[Windows 10]] as the successor to Windows 8.1. It was released on July 29, 2015, and addresses shortcomings in the user interface first introduced with Windows 8. Changes on PC include the return of the Start Menu, a [[virtual desktop]] system, and the ability to run Windows Store apps within windows on the desktop rather than in full-screen mode. [[Windows 10]] is said to be available to update from qualified [[Windows 7]] with SP1, [[Windows 8.1]] and [[Windows Phone 8.1]] devices from the Get Windows 10 Application (for [[Windows 7]], [[Windows 8.1]]) or [[Windows Update]] ([[Windows 7]]).<ref>{{Cite web |date=September 30, 2014 |title=Announcing Windows 10 – Windows Blog |url=http://blogs.windows.com/bloggingwindows/2014/09/30/announcing-windows-10/ |url-status=dead |archive-url=https://web.archive.org/web/20150910084428/https://blogs.windows.com/bloggingwindows/2014/09/30/announcing-windows-10/ |archive-date=September 10, 2015 |access-date=September 30, 2014 |df=mdy-all}}</ref>

In February 2017, Microsoft announced the migration of its Windows source code repository from [[Perforce]] to [[Git]]. This migration involved 3.5 million separate files in a 300-gigabyte repository.<ref name="PBright" /> By May 2017, 90 percent of its engineering team was using Git, in about 8500 commits and 1760 Windows builds per day.<ref name="PBright">{{Cite web |last=Bright |first=Peter |date=May 24, 2017 |title=Windows switch to Git almost complete: 8,500 commits and 1,760 builds each day |url=https://arstechnica.com/information-technology/2017/05/90-of-windows-devs-now-using-git-creating-1760-windows-builds-per-day/ |url-status=live |archive-url=https://web.archive.org/web/20170524171707/https://arstechnica.com/information-technology/2017/05/90-of-windows-devs-now-using-git-creating-1760-windows-builds-per-day/ |archive-date=May 24, 2017 |website=[[Ars Technica]] |publisher=[[Condé Nast]]}}</ref>

In June 2021, shortly before Microsoft's announcement of Windows 11, Microsoft updated their lifecycle policy pages for Windows 10, revealing that support for their last release of Windows 10 will end on October 14, 2025.<ref name="Windows10HomeAndProLifecycle">{{Cite web |title=Window 10 Home and Pro Lifecycle |url=https://docs.microsoft.com/en-us/lifecycle/products/windows-10-home-and-pro |url-status=live |archive-url=https://web.archive.org/web/20210610190436/https://docs.microsoft.com/en-us/lifecycle/products/windows-10-home-and-pro |archive-date=June 10, 2021 |access-date=July 2, 2021 |publisher=[[Microsoft]]}}</ref><ref name="Windows10EntAndEduLifecycle">{{Cite web |title=Window 10 Enterprise and Education Lifecycle |url=https://docs.microsoft.com/en-us/lifecycle/products/windows-10-enterprise-and-education |url-status=live |archive-url=https://web.archive.org/web/20210701160716/https://docs.microsoft.com/en-us/lifecycle/products/windows-10-enterprise-and-education |archive-date=July 1, 2021 |access-date=July 2, 2021 |publisher=[[Microsoft]]}}</ref> On April 27, 2023, Microsoft announced that version 22H2 would be the last of Windows 10.<ref name="winroadmapupdate">{{Cite web |last=Leznek |first=Jason |date=April 27, 2023 |title=Windows client roadmap update |url=https://techcommunity.microsoft.com/t5/windows-it-pro-blog/windows-client-roadmap-update/ba-p/3805227 |access-date=May 1, 2023 |website=Microsoft |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135714/https://techcommunity.microsoft.com/t5/windows-it-pro-blog/windows-client-roadmap-update-april-2023/ba-p/3805227 |url-status=live }}</ref><ref>{{Cite news |last=Bowden |first=Zack |date=April 27, 2023 |title=Windows 10 is finished — Microsoft confirms 'version 22H2' is the last |work=Windows Central |url=https://www.windowscentral.com/software-apps/windows-10/windows-10-is-finished-microsoft-confirms-version-22h2-is-the-last |access-date=May 1, 2023 |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135717/https://www.windowscentral.com/software-apps/windows-10/windows-10-is-finished-microsoft-confirms-version-22h2-is-the-last |url-status=live }}</ref>
[[File:Windows logo and wordmark - 2021.svg|thumb|Windows logo (2021–present)]]

===== Windows 11 =====
{{Main|Windows 11}}
On June 24, 2021, [[Windows 11]] was announced as the successor to Windows 10 during a livestream. The new operating system was designed to be more user-friendly and understandable. It was released on October 5, 2021.<ref>{{Cite web |last=Cox |first=George |title=Windows 11 release date is October 5 |url=https://www.thespectrum.com/story/news/local/mesquite/2021/09/13/pc-periodicals-windows-11-release-date-october-5/8316090002/ |url-status=live |archive-url=https://web.archive.org/web/20230218183810/https://www.thespectrum.com/story/news/local/mesquite/2021/09/13/pc-periodicals-windows-11-release-date-october-5/8316090002/ |archive-date=February 18, 2023 |access-date=September 18, 2021 |website=The Spectrum |language=en-US}}</ref><ref>{{Cite web |last=Warren |first=Tom |date=June 24, 2021 |title=Microsoft announces Windows 11, with a new design, Start menu, and more |url=https://www.theverge.com/2021/6/24/22546791/microsoft-windows-11-announcement-features-updates |url-status=live |archive-url=https://web.archive.org/web/20210624150725/https://www.theverge.com/2021/6/24/22546791/microsoft-windows-11-announcement-features-updates |archive-date=June 24, 2021 |access-date=June 24, 2021 |website=The Verge |language=en}}</ref> {{As of|2022|05|post=,}} Windows 11 is a free upgrade to Windows 10 users who meet the system requirements.<ref name="windows11specs">{{Cite web |title=Windows 11 Specs and System Requirements |url=https://www.microsoft.com/en-us/windows/windows-11-specifications |url-status=live |archive-url=https://web.archive.org/web/20220531013104/https://www.microsoft.com/en-us/windows/windows-11-specifications |archive-date=May 31, 2022 |access-date=May 31, 2022 |publisher=Microsoft}}</ref>

==== Windows 365 ====
{{See also|Azure Virtual Desktop}}
{{distinguish|Microsoft 365|Windows/386}}
In July 2021, Microsoft announced it will start selling subscriptions to virtualized Windows desktops as part of a new ''Windows 365'' service in the following month. The new service will allow for [[Cross-platform software|cross-platform usage]], aiming to make the operating system available for both Apple and Android users. It is a separate service and offers several variations including Windows 365 Frontline, Windows 365 Boot, and the Windows 365 app.<ref>{{Cite web |last=Warren |first=Tom |date=April 6, 2023 |title=Microsoft's Windows 365 Cloud PCs get more flexible, LG TV integration, and more |url=https://www.theverge.com/2023/4/6/23672363/microsoft-windows-365-frontline-lg-tv-integration-features |website=[[The Verge]] |access-date=June 2, 2023 |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135720/https://www.theverge.com/2023/4/6/23672363/microsoft-windows-365-frontline-lg-tv-integration-features |url-status=live }}</ref> The [[subscription service]] will be accessible through any [[operating system]] with a [[web browser]]. The new service is an attempt at capitalizing on the growing trend, fostered during the [[COVID-19 pandemic]], for businesses to adopt a hybrid [[remote work]] environment, in which "employees split their time between the office and home". As the service will be accessible through web browsers, Microsoft will be able to bypass the need to publish the service through [[Google Play]] or the [[App Store (Apple)|Apple App Store]].<ref>{{Cite web |last=Foley |first=Mary Jo |date=July 14, 2021 |title=Microsoft brings Windows to the cloud with Windows 365 and Cloud PC |url=https://www.zdnet.com/article/microsoft-brings-windows-to-the-cloud-with-windows-365-and-cloud-pc/ |url-status=live |archive-url=https://web.archive.org/web/20210728074255/https://www.zdnet.com/article/microsoft-brings-windows-to-the-cloud-with-windows-365-and-cloud-pc/ |archive-date=July 28, 2021 |access-date=July 14, 2021 |website=ZDNet}}</ref><ref>{{Cite news |last=Tilley |first=Aaron |date=July 14, 2021 |title=Microsoft Aims to Put Windows in Hands of Apple, Android Users Through Hybrid Work |work=[[The Wall Street Journal]] |url=https://www.wsj.com/articles/microsoft-aims-to-put-windows-in-hands-of-apple-android-users-through-hybrid-work-11626274801 |url-status=live |url-access=subscription |access-date=July 15, 2021 |archive-url=https://web.archive.org/web/20210728132315/https://www.wsj.com/articles/microsoft-aims-to-put-windows-in-hands-of-apple-android-users-through-hybrid-work-11626274801 |archive-date=July 28, 2021 |issn=0099-9660}}</ref><ref>{{Cite news |last=Higgins |first=Tim |date=June 23, 2021 |title=Apple's Fight for Control Over Apps Moves to Congress and EU |work=[[The Wall Street Journal]] |url=https://www.wsj.com/articles/apples-fight-for-control-over-apps-moves-to-congress-and-eu-11624440601 |url-status=live |url-access=subscription |access-date=July 15, 2021 |archive-url=https://web.archive.org/web/20210728075524/https://www.wsj.com/articles/apples-fight-for-control-over-apps-moves-to-congress-and-eu-11624440601 |archive-date=July 28, 2021 |issn=0099-9660}}</ref><ref>{{Cite web |title=Microsoft unveils Windows 365, a Windows 10 PC in the cloud |url=https://www.engadget.com/windows-365-cloud-virtual-pc-150022333.html |url-status=live |archive-url=https://web.archive.org/web/20210728080818/https://www.engadget.com/windows-365-cloud-virtual-pc-150022333.html |archive-date=July 28, 2021 |access-date=July 15, 2021 |website=Engadget |date=July 14, 2021 |language=en-US}}</ref><ref>{{Cite web |title=Windows 365 Cloud PC {{!}} Microsoft |url=https://www.microsoft.com/en-us/windows-365 |url-status=live |archive-url=https://web.archive.org/web/20210728090712/https://www.microsoft.com/en-us/windows-365 |archive-date=July 28, 2021 |access-date=July 15, 2021 |website=www.microsoft.com |language=en-us}}</ref>

Microsoft announced Windows 365 availability to business and enterprise customers on August 2, 2021.<ref>{{Cite web |last=Hill |first=Paul |date=August 2, 2021 |title=Microsoft announces the general availability of Windows 365 |url=https://www.neowin.net/news/microsoft-announces-the-general-availability-of-windows-365/ |url-status=live |archive-url=https://web.archive.org/web/20210802173719/https://www.neowin.net/news/microsoft-announces-the-general-availability-of-windows-365/ |archive-date=August 2, 2021 |access-date=August 2, 2021 |website=Neowin}}</ref>

==== Multilingual support ====
{{see also|Multilingual User Interface}}

Multilingual support has been built into Windows since Windows 3.0. The language for both the keyboard and the interface can be changed through the Region and Language Control Panel. Components for all supported input languages, such as [[Input Method Editor]]s, are automatically installed during Windows installation (in Windows XP and earlier, files for East Asian languages, such as Chinese, and files for right-to-left scripts, such as Arabic, may need to be installed separately, also from the said Control Panel). Third-party IMEs may also be installed if a user feels that the provided one is insufficient for their needs. Since Windows 2000, English editions of Windows NT have East Asian IMEs (such as Microsoft Pinyin IME and Microsoft Japanese IME) bundled, but files for East Asian languages may be manually installed on Control Panel.

Interface languages for the operating system are free for download, but some languages are limited to certain editions of Windows. [[Language Interface Pack]]s (LIPs) are redistributable and may be downloaded from Microsoft's Download Center and installed for any edition of Windows (XP or later){{snd}}they translate most, but not all, of the Windows interface, and require a certain base language (the language which Windows originally shipped with). This is used for most languages in emerging markets. Full Language Packs, which translate the complete operating system, are only available for specific editions of Windows (Ultimate and Enterprise editions of Windows Vista and 7, and all editions of Windows 8, 8.1 and RT except Single Language). They do not require a specific base language and are commonly used for more popular languages such as French or Chinese. These languages cannot be downloaded through the Download Center, but are available as optional updates through the [[Windows Update]] service (except Windows 8).

The interface language of installed applications is not affected by changes in the Windows interface language. The availability of languages depends on the application developers themselves.

[[Windows 8]] and [[Windows Server 2012]] introduce a new Language Control Panel where both the interface and input languages can be simultaneously changed, and language packs, regardless of type, can be downloaded from a central location. The PC Settings app in [[Windows 8.1]] and [[Windows Server 2012 R2]] also includes a counterpart settings page for this. Changing the interface language also changes the language of preinstalled [[Windows Store]] apps (such as Mail, Maps and News) and certain other Microsoft-developed apps (such as Remote Desktop). The above limitations for language packs are however still in effect, except that full language packs can be installed for any edition except Single Language, which caters to emerging markets.

==== Platform support ====
Windows NT included support for several platforms before the [[x86]]-based [[personal computer]] became dominant in the professional world. [[Windows NT 4.0]] and its predecessors supported [[PowerPC]], [[DEC Alpha]] and [[MIPS architecture|MIPS]] R4000 (although some of the platforms implement [[64-bit computing]], the OS treated them as 32-bit). Windows 2000 dropped support for all platforms, except the third generation x86 (known as [[IA-32]]) or newer in 32-bit mode. The client line of the Windows NT family still ran on IA-32 up to [[Windows 10]]<ref name="windows11specs" /> (the server line of the Windows NT family still ran on IA-32 up to [[Windows Server 2008]]).

With the introduction of the Intel Itanium architecture ([[IA-64]]), Microsoft released new versions of Windows to support it. Itanium versions of [[Windows XP]] and [[Windows Server 2003]] were released at the same time as their mainstream x86 counterparts. Windows XP 64-Bit Edition (Version 2003), released in 2003, is the last Windows client operating system to support Itanium. Windows Server line continues to support this platform until [[Windows Server 2012]]; Windows Server 2008 R2 is the last Windows operating system to support Itanium architecture.

On April 25, 2005, Microsoft released [[Windows XP Professional x64 Edition]] and Windows Server 2003 x64 editions to support [[x86-64]] (or simply x64), the 64-bit version of x86 architecture. [[Windows Vista]] was the first client version of Windows NT to be released simultaneously in IA-32 and x64 editions. As of 2024, x64 is still supported.

An edition of Windows 8 known as [[Windows RT]] was specifically created for computers with [[ARM architecture family|ARM architecture]], and while ARM is still used for Windows smartphones with Windows 10, tablets with Windows RT will not be updated. Starting from [[Windows 10 Fall Creators Update]] (version 1709) and later includes support for ARM-based PCs.<ref>{{Cite web |last=Bott |first=Ed |date=October 7, 2019 |title=Windows 10 on Arm: What you need to know before you buy a Surface Pro X |url=https://www.zdnet.com/article/windows-10-on-arm-what-you-need-to-know-before-you-buy-a-surface-pro-x/ |url-status=live |archive-url=https://web.archive.org/web/20210701045005/https://www.zdnet.com/article/windows-10-on-arm-what-you-need-to-know-before-you-buy-a-surface-pro-x/ |archive-date=July 1, 2021 |access-date=June 14, 2021 |website=[[ZDNet]]}}</ref>

=== Windows CE ===
{{Main|Windows CE|Windows Phone}}

Windows CE (officially known as ''Windows Embedded Compact''), is an edition of Windows that runs on [[Handheld PC|minimalistic computers]], like satellite navigation systems and some mobile phones. Windows Embedded Compact is based on its own dedicated kernel, dubbed Windows CE kernel. Microsoft licenses Windows CE to [[OEM]]s and device makers. The OEMs and device makers can modify and create their own user interfaces and experiences, while Windows CE provides the technical foundation to do so.

Windows CE was used in the [[Dreamcast]] along with Sega's own proprietary OS for the console. Windows CE was the core from which [[Windows Mobile]] was derived. Its successor, [[Windows Phone 7]], was based on components from both [[Windows Embedded CE 6.0|Windows CE 6.0 R3]] and [[Windows Embedded Compact 7|Windows CE 7.0]]. [[Windows Phone 8]] however, is based on the same NT-kernel as Windows 8.

Windows Embedded Compact is not to be confused with [[Windows XP Embedded]] or [[Windows NT 4.0 Embedded]], modular editions of Windows based on Windows NT kernel.

=== Xbox OS ===
{{Main|Xbox system software}}
Xbox OS is an unofficial name given to the version of Windows that runs on [[Xbox]] consoles.<ref>{{Cite web |last=Anand Lal Shimpi |title=The Xbox One – Mini Review & Comparison to Xbox 360/PS4 |url=http://www.anandtech.com/show/7528/the-xbox-one-mini-review-hardware-analysis |url-status=dead |archive-url=https://web.archive.org/web/20141012063931/http://www.anandtech.com/show/7528/the-xbox-one-mini-review-hardware-analysis |archive-date=October 12, 2014 |access-date=October 21, 2014 |website=anandtech.com}}</ref> From [[Xbox One]] onwards it is an implementation with an emphasis on virtualization (using [[Hyper-V]]) as it is three operating systems running at once, consisting of the core [[operating system]], a second implemented for games and a more Windows-like environment for applications.<ref name="xboxonethreesystems">{{Cite web |title=Xbox One: Hardware and software specs detailed and analyzed – Three operating systems in one |url=http://www.extremetech.com/gaming/156467-xbox-one-hardware-and-software-specs-detailed-and-analyzed |url-status=dead |archive-url=https://web.archive.org/web/20131116221155/http://www.extremetech.com/gaming/156467-xbox-one-hardware-and-software-specs-detailed-and-analyzed |archive-date=November 16, 2013 |access-date=December 1, 2013 |publisher=ExtremeTech}}</ref>
Microsoft updates Xbox One's OS every month, and these updates can be downloaded from the Xbox Live service to the Xbox and subsequently installed, or by using offline recovery images downloaded via a PC.<ref>{{Cite web |title=How to use the Offline System Update Diagnostic Tool on Xbox One |url=http://support.xbox.com/xbox-one/system/offline-system-update-diagnostic-tool |url-status=dead |archive-url=https://web.archive.org/web/20210427233154/https://support.xbox.com/xbox-one/system/offline-system-update-diagnostic-tool |archive-date=April 27, 2021 |access-date=November 30, 2013 |website=Xbox Official Site |publisher=Microsoft}}</ref> It was originally based on NT 6.2 (Windows 8) kernel, and the latest version runs on an NT 10.0 base. This system is sometimes referred to as "Windows 10 on Xbox One".<ref>{{Cite web |title=Xbox One Is "Literally a Windows Device" |url=http://www.gamespot.com/articles/xbox-one-is-literally-a-windows-device/1100-6430425/ |url-status=live |archive-url=https://web.archive.org/web/20151227060719/http://www.gamespot.com/articles/xbox-one-is-literally-a-windows-device/1100-6430425/ |archive-date=December 27, 2015 |website=GameSpot}}</ref><ref>{{Cite web |title=New Xbox One Update Will Make Some Functionality 50 Percent Faster |url=http://www.gamespot.com/articles/new-xbox-one-update-will-make-some-functionality-5/1100-6430524/ |url-status=live |archive-url=https://web.archive.org/web/20160202102914/http://www.gamespot.com/articles/new-xbox-one-update-will-make-some-functionality-5/1100-6430524/ |archive-date=February 2, 2016 |website=GameSpot}}</ref>
Xbox One and [[Xbox Series X and Series S|Xbox Series]] operating systems also allow limited (due to licensing restrictions and testing resources) backward compatibility with previous generation hardware,<ref>{{Cite web |last=Tom Warren |date=June 16, 2015 |title=Xbox One dashboard update includes a huge new design and Cortana |url=https://www.theverge.com/2015/6/15/8786501/microsoft-xbox-one-dashboard-update-features |url-status=live |archive-url=https://web.archive.org/web/20170708210651/https://www.theverge.com/2015/6/15/8786501/microsoft-xbox-one-dashboard-update-features |archive-date=July 8, 2017 |website=The Verge |publisher=Vox Media}}</ref> and the Xbox 360's system is backwards compatible with the original Xbox.<ref>{{Cite web |last=Eric Qualls |title=Xbox 360 and Xbox Games Backwards Compatibility |url=http://xbox.about.com/od/xbox360faqs/f/x360bcfaq.htm |url-status=live |archive-url=https://web.archive.org/web/20150928070914/http://xbox.about.com/od/xbox360faqs/f/x360bcfaq.htm |archive-date=September 28, 2015 |website=About.com Tech}}</ref>

== Version control system ==
Up to and including every version before [[Windows 2000]], Microsoft used an in-house version control system named Source Library Manager (SLM). Shortly after Windows 2000 was released, Microsoft switched to a fork of Perforce named Source Depot.<ref>{{Cite web |last=Chen |first=Raymond |date=January 22, 2018 |title=The history of change-packing tools at Microsoft (so far) |url=https://devblogs.microsoft.com/oldnewthing/20180122-00/?p=97855 |url-status=live |archive-url=https://web.archive.org/web/20220525102009/https://devblogs.microsoft.com/oldnewthing/20180122-00/?p=97855 |archive-date=May 25, 2022 |access-date=September 2, 2023 |website=The Old New Thing |publisher=Microsoft Developer Blogs (DevBlogs)}}</ref> This system was used up until 2017 once the system could not keep up with the size of Windows.{{Citation needed|date=September 2023}} Microsoft had begun to integrate Git into [[Team Foundation Server]] in 2013,<ref>{{Cite web |last=Lewis |first=Andy |date=2013-06-26 |title=Visual Studio 2013 Preview: Git version control and Team Foundation Build |url=https://devblogs.microsoft.com/devops/visual-studio-2013-preview-git-version-control-and-team-foundation-build/ |access-date=2023-09-02 |website=Azure DevOps Blog |publisher=Microsoft Developer Blogs (DevBlogs) |language=en-US |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135727/https://devblogs.microsoft.com/devops/visual-studio-2013-preview-git-version-control-and-team-foundation-build/ |url-status=live }}</ref> but Windows (and Office) continued to rely on Source Depot.<ref>{{Cite web |last=Harry |first=Brian |date=2017-02-03 |title=Scaling Git (and some back story) |url=https://devblogs.microsoft.com/bharry/scaling-git-and-some-back-story/ |access-date=2023-09-02 |website=Brian Harry's Blog |publisher=Microsoft Developer Blogs (DevBlogs) |language=en-US |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135724/https://devblogs.microsoft.com/bharry/scaling-git-and-some-back-story/ |url-status=live }}</ref> The Windows code was divided among 65 different repositories with a kind of virtualization layer to produce unified view of all of the code.{{Citation needed|date=September 2023}}

In 2017 Microsoft announced that it would start using [[Git]], an open source version control system created by [[Linus Torvalds]], and in May 2017 they reported that the migration into a new Git repository was complete.<ref name="PBright" /><ref>{{Cite web |date=May 24, 2017 |title=The largest Git repo on the planet |url=https://devblogs.microsoft.com/bharry/the-largest-git-repo-on-the-planet/ |url-status=live |archive-url=https://web.archive.org/web/20211006233017/https://devblogs.microsoft.com/bharry/the-largest-git-repo-on-the-planet/ |archive-date=October 6, 2021 |access-date=October 8, 2021 |website=Brian Harry's Blog |language=en-US}}</ref><ref name=":0" />

=== VFSForGit ===
Each Git repository contains a complete history of all the files, which tends to be very large for Windows.<ref>{{Cite book |last1=Chacon |first1=Scott |last2=Straub |first2=Ben |date=2014 |title=Pro Git |publisher=Apress |others=The version found here has been updated with corrections and additions from hundreds of contributors. |isbn=978-1-4842-0077-3 |edition=2nd |chapter=2.1 Git Basics – Getting a Git Repository: Cloning an Existing Repository |chapter-url=https://git-scm.com/book/en/v2/Git-Basics-Getting-a-Git-Repository#_git_cloning |via=the Git Project |access-date=September 2, 2023 |archive-date=September 1, 2023 |archive-url=https://web.archive.org/web/20230901193044/https://git-scm.com/book/en/v2/Git-Basics-Getting-a-Git-Repository#_git_cloning |url-status=live }}</ref> Microsoft has been working on a new project called the [[Virtual File System for Git]] (VFSForGit) to address these challenges.<ref name=":0">{{Cite web |last=Bright |first=Peter |date=February 6, 2017 |title=Microsoft hosts the Windows source in a monstrous 300&nbsp;GB Git repository |url=https://arstechnica.com/information-technology/2017/02/microsoft-hosts-the-windows-source-in-a-monstrous-300gb-git-repository/ |url-status=live |archive-url=https://web.archive.org/web/20171226073905/https://arstechnica.com/information-technology/2017/02/microsoft-hosts-the-windows-source-in-a-monstrous-300gb-git-repository/ |archive-date=December 26, 2017 |access-date=December 26, 2017 |website=Ars Technica |df=mdy-all }}</ref>

In 2021 the VFS for Git was superseded by '''Scalar'''.<ref>{{Cite web |last=Stolee |first=Derrick |date=May 28, 2020 |title=Frequently Asked Questions: Why Are You Abandoning VFS for Git? |url=https://github.com/microsoft/VFSForGit/blob/3790eb06e14d88d71af11958414b59fd3cb2e65d/docs/faq.md#why-are-you-abandoning-vfs-for-git |website=GitHub |publisher=Microsoft |archive-date=May 1, 2023 |archive-url=https://web.archive.org/web/20230501123753/https://github.com/microsoft/VFSForGit/blob/3790eb06e14d88d71af11958414b59fd3cb2e65d/docs/faq.md#why-are-you-abandoning-vfs-for-git |url-status=live |access-date=2023-09-02 }}</ref>

== Timeline of releases ==

{{mw-datatable}}
{| class="wikitable mw-datatable"
|+ Table of Windows versions
|-
! rowspan="2" | Product name
! rowspan="2" | Latest version
! rowspan="2" | [[General availability]] date
! rowspan="2" | Codename
! colspan="2" | Support until<ref>{{Cite web |title=Microsoft Support Lifecycle |url=http://support.microsoft.com/lifecycle/ |url-status=live |archive-url=https://web.archive.org/web/20081011144824/http://support.microsoft.com/lifecycle/ |archive-date=October 11, 2008 |publisher=Microsoft}}</ref>
! colspan="3" | Latest version of
|-
! Mainstream
! Extended
! style="width:50px;" | [[Internet Explorer|IE]]
! style="width:50px;" | [[DirectX]]
! style="width:50px;" | [[Microsoft Edge|Edge]]
|-
| {{version|o|[[Windows 1.0]]|show=|sortKey=1.0}}
| 1.04
| November 20, 1985
| Interface Manager
| colspan="2" rowspan="6" align="center" | December 31, 2001
| rowspan="4" {{N/A}}
| rowspan="11" {{N/A}}
| rowspan="25" {{N/A}}
|-
| {{version|o|[[Windows 2.0]]|show=|sortKey=2.0}}
| 2.03
| December 9, 1987
| {{N/A}}
|-
| {{version|o|[[Windows 2.1]]|show=|sortKey=2.1}}
| 2.11
| May 27, 1988
| {{N/A}}
|-
| {{version|o|[[Windows 3.0]]|show=|sortKey=3.0}}
| 3.0
| May 22, 1990
| {{N/A}}
|-
| {{version|o|[[Windows 3.1]]|show=|sortKey=3.1}}
| 3.1
| April 6, 1992
| {{N/A}}
| rowspan="2" | [[Internet Explorer 5|5]]
|-
| {{version|o|[[Windows 3.1x|Windows For Workgroups 3.1]]|show=|sortKey=3.101}}
| 3.1
| October 1992
| Sparta, Winball
|-
| {{version|o|[[Windows NT 3.1]]|show=|sortKey=NT 3.1}}
| NT 3.1.528
| July 27, 1993
| {{N/A}}
| colspan="2" align="center" | December 31, 2000
| [[Internet Explorer 2|2]]
|-
| {{version|o|[[Windows 3.1x|Windows For Workgroups 3.11]]|show=|sortKey=3.111}}
| 3.11
| August 11, 1993
| Sparta, Winball
| colspan="2" rowspan="4" align="center" | December 31, 2001
| rowspan="2" | [[Internet Explorer 5|5]]
|-
| {{version|o|[[Windows 3.1x|Windows 3.2]]|show=|sortKey=3.2}}
| 3.2
| November 22, 1993
| {{N/A}}
|-
| {{version|o|[[Windows NT 3.5]]|show=|sortKey=NT 3.5}}
| NT 3.5.807
| September 21, 1994
| Daytona
| [[Internet Explorer 3|3]]
|-
| {{version|o|[[Windows NT 3.51]]|show=|sortKey=NT 3.51}}
| NT 3.51.1057
| May 30, 1995
| {{N/A}}
| [[Internet Explorer 5|5]]
|-
| {{version|o|[[Windows 95]]|show=|sortKey=4.0}}
| 4.0.950
| August 24, 1995
| Chicago, 4.0
| align="center" | December 31, 2000
| align="center" | December 31, 2001
| [[Internet Explorer 5|5.5]]
| 8.0a
|-
| {{version|o|[[Windows NT 4.0]]|show=|sortKey=NT 4.0}}
| NT 4.0.1381
| July 31, 1996
| Cairo
| align="center" rowspan="3" | June 30, 2002
| align="center" | June 30, 2004
| rowspan="5" | [[Internet Explorer 6|6]]
| 3.0a
|-
| {{version|o|[[Windows 98]]|show=|sortKey=4.10}}
| 4.10.1998
| June 25, 1998
| Memphis, 97, 4.1
| align="center" rowspan="2" | July 11, 2006
| rowspan="9" | 9.0c
|-
| {{version|o|[[Windows 98 SE]]|show=|sortKey=4.11}}
| 4.10.2222
| May 5, 1999
| {{N/A}}
|-
| {{version|o|[[Windows 2000]]|show=|sortKey=NT 5.0}}
| NT 5.0.2195
| February 17, 2000
| {{N/A}}
| align="center" | June 30, 2005
| align="center" | July 13, 2010
|-
| {{version|o|[[Windows Me]]|show=|sortKey=4.90}}
| 4.90.3000
| September 14, 2000
| Millennium, 4.9
| align="center" | December 31, 2003
| align="center" | July 11, 2006
|-
| {{version|o|[[Windows XP]]|show=|sortKey=NT 5.1}}
| NT 5.1.2600
| October 25, 2001
| Whistler
| align="center" rowspan="2" | April 14, 2009
| align="center" rowspan="2" | April 8, 2014
| rowspan="5" | [[Internet Explorer 8|8]]
|-
| {{version|o|[[Windows XP 64-bit Edition]]|show=|sortKey=NT 5.21}}
| rowspan="3" | NT 5.2.3790
| March 28, 2003
| {{N/A}}
|-
| {{version|o|[[Windows Server 2003]]|show=|sortKey=NT 5.22}}
| April 24, 2003
| Whistler Server
| align="center" | July 13, 2010
| align="center" | July 14, 2015
|-
| {{version|o|[[Windows XP Professional x64 Edition]]|show=|sortKey=NT 5.23}}
| April 25, 2005
| {{N/A}}
| align="center" rowspan="2" | April 14, 2009
| align="center" rowspan="2" | April 8, 2014
|-
| {{version|o|[[Windows Fundamentals for Legacy PCs]]|show=|sortKey=NT 5.24}}
| NT 5.1.2600
| July 8, 2006
| Eiger, Mönch
|-
| {{version|o|[[Windows Vista]]|show=|sortKey=NT 6.0}}
| NT 6.0.6003
| January 30, 2007
| Longhorn
| align="center" | April 10, 2012
| align="center" | April 11, 2017
| [[Internet Explorer 9|9]]
| 11
|-
| {{version|o|[[Windows Home Server]]|show=|sortKey=NT 5.25}}
| NT 5.2.4500
| November 4, 2007
| Quattro
| colspan="2" align="center" | January 8, 2013
| [[Internet Explorer 8|8]]
| 9.0c
|-
| {{version|o|[[Windows Server 2008]]|show=|sortKey=NT 6.01}}
| NT 6.0.6003
| February 27, 2008
| Longhorn Server
| align="center" rowspan="3" | January 13, 2015
| align="center" rowspan="3" | January 14, 2020
| [[Internet Explorer 9|9]]
| rowspan="4" | 11
|-
| {{version|o|[[Windows 7]]|show=|sortKey=NT 6.1}}
| rowspan="2" | NT 6.1.7601
| October 22, 2009
| Windows 7<ref>{{Cite web |last=Chen |first=Raymond |date=July 22, 2019 |title=What was the code name for Windows 7? |url=https://devblogs.microsoft.com/oldnewthing/20190722-00/?p=102724 |url-status=live |archive-url=https://web.archive.org/web/20210926093909/https://devblogs.microsoft.com/oldnewthing/20190722-00/?p=102724 |archive-date=September 26, 2021 |access-date=October 6, 2021 |website=The Old New Thing}}</ref>
| rowspan="4" | [[Internet Explorer 11|11]]
| rowspan="7" | 109
|-
| {{version|o|[[Windows Server 2008 R2]]|show=|sortKey=NT 6.11}}
| October 22, 2009
| Windows Server 7
|-
| {{version|o|[[Windows Home Server 2011]]|show=|sortKey=NT 6.12}}
| NT 6.1.8400
| April 6, 2011
| Vail
| colspan="2" align="center" | April 12, 2016
|-
| {{version|o|[[Windows Server 2012]]|show=|sortKey=NT 6.21}}
| rowspan="2" | NT 6.2.9200
| September 4, 2012
| Server 8
| align="center" | October 9, 2018
| align="center" | October 10, 2023
| rowspan="2" | 11.1
|-
| {{version|o|[[Windows 8]]|show=|sortKey=NT 6.22}}
| October 26, 2012
| {{N/A}}
| colspan="2" align="center" | January 12, 2016
| [[Internet Explorer 10|10]]
|-
| {{version|o|[[Windows 8.1]]|show=|sortKey=NT 6.31}}
| rowspan="2" | NT 6.3.9600
| October 17, 2013
| Blue
| align="center" | January 9, 2018
| align="center" | January 10, 2023
| rowspan="6" | [[Internet Explorer 11|11]]
| rowspan="2" | 11.2
|-
| {{version|o|[[Windows Server 2012 R2]]|show=|sortKey=NT 6.32}}
| October 18, 2013
| Server Blue
| align="center" | October 9, 2018
| align="center" | October 10, 2023
|-
| {{version|co|[[Windows 10]]|show=|sortKey=NT 10.01}}
| NT 10.0.19045
| July 29, 2015
| ''[[Windows 10#Updates and support|Various]]''
| colspan="2" align="center" | October 14, 2025<ref name="Windows10HomeAndProLifecycle" /><ref name="Windows10EntAndEduLifecycle" />
| rowspan="6" | 12
| rowspan="6" | 136
|-
| {{version|co|[[Windows Server 2016]]|show=|sortKey=NT 10.02}}
| NT 10.0.14393
| October 12, 2016
| {{N/A}}
| align="center" | January 11, 2022
| align="center" | January 12, 2027
|-
| {{version|co|[[Windows Server 2019]]|show=|sortKey=NT 10.03}}
| NT 10.0.17763
| October 2, 2018
| {{N/A}}
| align="center" | January 9, 2024
| align="center" | January 9, 2029
|-
| {{version|co|[[Windows Server 2022]]|show=|sortKey=NT 10.11}}
| NT 10.0.20348
| August 18, 2021
| {{N/A}}
| align="center" | October 13, 2026
| align="center" | October 14, 2031
|-
| {{version|c|[[Windows 11]]|show=|sortKey=NT 10.12}}
| NT 10.0.26100
| October 5, 2021
| ''[[Windows 11#Updates and support|Various]]''
| align="center" colspan="2" | October 12, 2027<ref>{{Cite web |date=20 September 2022 |title=Windows 11 Home and Pro Product Life Cycle |url=https://learn.microsoft.com/en-us/lifecycle/products/windows-11-enterprise-and-education |access-date=February 14, 2023 |website=Microsoft |language=English |archive-date=March 21, 2023 |archive-url=https://web.archive.org/web/20230321051025/https://learn.microsoft.com/en-us/lifecycle/products/windows-11-enterprise-and-education |url-status=live }}</ref>
| rowspan="2" {{N/A}}
|-
| {{version|c|[[Windows Server 2025]]|show=|sortKey=NT 10.13}}
| NT 10.0.26100
| November 1, 2024
| {{N/A}}
| October 9, 2029
| October 10, 2034
|-
| colspan="9" | {{Version|l||show=111110}}
|}

{{Timeline Windows}}

{{Wide image|Suite des versions de Windows.svg|700px|The Windows family tree|100%|center}}

== Usage share and device sales ==
{{Main|Usage share of operating systems}}
{{Windows usage share}}

Use of [[Windows 10]] has exceeded Windows 7 globally since early 2018.<ref>{{Cite web |title=Desktop Windows Version Market Share Worldwide {{!}} StatCounter Global Stats |url=https://gs.statcounter.com/windows-version-market-share/desktop/worldwide/#monthly-201706-201806 |url-status=live |archive-url=https://web.archive.org/web/20190420180627/http://gs.statcounter.com/windows-version-market-share/desktop/worldwide#monthly-201706-201806 |archive-date=April 20, 2019 |access-date=November 24, 2019 |website=StatCounter Global Stats |language=en}}</ref>

For desktop and laptop computers, according to [[Net Applications]] and [[StatCounter]] (which track the use of operating systems in devices that are active on the Web), Windows was the most used operating-system family in August 2021, with around 91% usage share according to Net Applications<ref>{{Cite web |title=Desktop Operating system market share: August 2021 |url=https://www.netmarketshare.com/operating-system-market-share.aspx?options=%7B%22filter%22%3A%7B%22%24and%22%3A%5B%7B%22deviceType%22%3A%7B%22%24in%22%3A%5B%22Desktop%2Flaptop%22%5D%7D%7D%5D%7D%2C%22dateLabel%22%3A%22Custom%22%2C%22attributes%22%3A%22share%22%2C%22group%22%3A%22platform%22%2C%22sort%22%3A%7B%22share%22%3A-1%7D%2C%22id%22%3A%22platformsDesktop%22%2C%22dateInterval%22%3A%22Monthly%22%2C%22dateStart%22%3A%222021-08%22%2C%22dateEnd%22%3A%222021-08%22%2C%22segments%22%3A%22-1000%22%7D |url-status=live |archive-url=https://web.archive.org/web/20210908052821/https://www.netmarketshare.com/operating-system-market-share.aspx?options=%7B%22filter%22%3A%7B%22%24and%22%3A%5B%7B%22deviceType%22%3A%7B%22%24in%22%3A%5B%22Desktop%2Flaptop%22%5D%7D%7D%5D%7D%2C%22dateLabel%22%3A%22Custom%22%2C%22attributes%22%3A%22share%22%2C%22group%22%3A%22platform%22%2C%22sort%22%3A%7B%22share%22%3A-1%7D%2C%22id%22%3A%22platformsDesktop%22%2C%22dateInterval%22%3A%22Monthly%22%2C%22dateStart%22%3A%222021-08%22%2C%22dateEnd%22%3A%222021-08%22%2C%22segments%22%3A%22-1000%22%7D |archive-date=September 8, 2021 |access-date=September 8, 2021 |website=[[Net Applications]]}}</ref> and around 76% usage share according to StatCounter.<ref>{{Cite web |title=Desktop Operating System Market Share Worldwide: August 2021 |url=https://gs.statcounter.com/os-market-share/desktop/worldwide/#monthly-202108-202108-bar |url-status=live |archive-url=https://archive.today/20200127171354/https://gs.statcounter.com/os-market-share/desktop/worldwide/%23monthly-202001-202001-bar#monthly-202108-202108-bar |archive-date=January 27, 2020 |access-date=September 8, 2021 |website=[[StatCounter]]}}</ref>

Including personal computers of all kinds (e.g., desktops, laptops, mobile devices, and game consoles), Windows OSes accounted for 32.67% of usage share in August 2021, compared to Android (highest, at 46.03%), [[iOS]]'s 13.76%, [[iPadOS]]'s 2.81%, and macOS's 2.51%, according to Net Applications<ref>{{Cite web |title=Operating system market share: August 2021 |url=https://www.netmarketshare.com/operating-system-market-share.aspx?options=%7B%22filter%22%3A%7B%7D%2C%22dateLabel%22%3A%22Custom%22%2C%22attributes%22%3A%22share%22%2C%22group%22%3A%22platform%22%2C%22sort%22%3A%7B%22share%22%3A-1%7D%2C%22id%22%3A%22platformsDesktop%22%2C%22dateInterval%22%3A%22Monthly%22%2C%22dateStart%22%3A%222021-08%22%2C%22dateEnd%22%3A%222021-08%22%2C%22segments%22%3A%22-1000%22%7D |url-status=live |archive-url=https://web.archive.org/web/20210908054054/https://www.netmarketshare.com/operating-system-market-share.aspx?options=%7B%22filter%22:%7B%7D,%22dateLabel%22:%22Custom%22,%22attributes%22:%22share%22,%22group%22:%22platform%22,%22sort%22:%7B%22share%22:-1%7D,%22id%22:%22platformsDesktop%22,%22dateInterval%22:%22Monthly%22,%22dateStart%22:%222021-08%22,%22dateEnd%22:%222021-08%22,%22segments%22:%22-1000%22%7D |archive-date=September 8, 2021 |access-date=September 8, 2021 |website=[[Net Applications]]}}</ref> and 30.73% of usage share in August 2021, compared to Android (highest, at 42.56%), iOS/iPadOS's 16.53%, and macOS's 6.51%, according to StatCounter.<ref>{{Cite web |title=Operating System Market Share Worldwide: August 2021 |url=https://gs.statcounter.com/os-market-share#monthly-202108-202108-bar |url-status=live |archive-url=https://web.archive.org/web/20200215213114/https://gs.statcounter.com/os-market-share#monthly-202108-202108-bar |archive-date=February 15, 2020 |access-date=September 8, 2021 |website=[[StatCounter]]}}</ref>

Those statistics do not include servers (including [[cloud computing]], where Linux has significantly more market share than Windows) as Net Applications and StatCounter use web browsing as a proxy for all use.

== Security ==
{{update section|date=May 2020}}
Early versions of Windows were designed at a time where [[malware]] and networking were less common, and had few built-in security features; they did not provide access privileges to allow a user to prevent other users from accessing their files, and they did not provide [[memory protection]] to prevent one process from reading or writing another process's address space or to prevent a process from code or data used by privileged-mode code.

While the [[Windows 9x]] series offered the option of having profiles for multiple users with separate profiles and home folders, it had no concept of [[Principle of least privilege|access privileges]], allowing any user to edit others' files. In addition, while it ran separate 32-bit applications in separate address spaces, protecting an application's code and data from being read or written by another application, it did not protect the first megabyte of memory from [[Userland (computing)|userland]] applications for compatibility reasons. This area of memory contains code critical to the functioning of the operating system, and by writing into this area of memory an application can [[Crash (computing)|crash]] or [[Hang (computing)|freeze]] the operating system. This was a source of instability as faulty applications could accidentally write into this region, potentially corrupting important operating system memory, which usually resulted in some form of system error and halt.<ref>{{Cite web |date=November 21, 2001 |title=Transcript: Chat with Ed Bott and Carl Siechert, Co-Authors of Microsoft Windows XP Inside Out |url=http://www.microsoft.com/windowsxp/expertzone/chats/transcripts/bottchat.mspx |archive-url=https://web.archive.org/web/20040918191218/http://www.microsoft.com/windowsxp/expertzone/chats/transcripts/bottchat.mspx |archive-date=September 18, 2004 |access-date=April 20, 2019 |publisher=[[Microsoft]]}}</ref>

[[Windows NT]] was far more secure, implementing access privileges and full memory protection, and, while 32-bit programs meeting the DoD's C2 security rating,<ref>{{Cite news |last=Russinovich |first=Mark |date=Apr 30, 1998 |title=Windows NT Security, Part 1 |language=en |work=ITPro Today |url=https://www.itprotoday.com/security/windows-nt-security-part-1 |url-status=live |access-date=2022-09-29 |archive-url=https://web.archive.org/web/20220929082011/https://www.itprotoday.com/security/windows-nt-security-part-1 |archive-date=September 29, 2022}}</ref> yet these advantages were nullified{{Synthesis inline|date=November 2023}} by the fact that, prior to [[Windows Vista]], the default user account created during the setup process was an [[Windows administrator|administrator]] account; the user, and any program the user launched, had full access to the machine. Though [[Windows XP]] did offer an option of turning administrator accounts into limited accounts, the majority of home users did not do so, partially due to the number of programs which required administrator rights to function properly. As a result, most home users still ran as administrator all the time. These architectural flaws, combined with Windows's very high popularity, made Windows a frequent target of [[computer worm]] and [[Computer virus|virus]] writers.<ref>{{Cite web |last=Bruce Schneier |author-link=Bruce Schneier |date=June 15, 2005 |title=Crypto-Gram Newsletter |url=http://www.schneier.com/crypto-gram-0506.html |website=Schneier.com |url-status=dead |archive-url=https://web.archive.org/web/20070606070525/http://www.schneier.com/crypto-gram-0506.html |archive-date=June 6, 2007 |access-date=April 22, 2007 |publisher=[[BT Counterpane|Counterpane Internet Security, Inc.]]}}</ref><ref name="Patrizio2">{{Cite web |last=Andy Patrizio |date=April 27, 2006 |title=Linux Malware On The Rise |url=http://www.internetnews.com/dev-news/article.php/3601946 |url-status=live |archive-url=https://web.archive.org/web/20120205070731/http://www.internetnews.com/dev-news/article.php/3601946 |archive-date=February 5, 2012 |access-date=January 3, 2011 |website=InternetNews |publisher=[[QuinStreet]]}}</ref><ref>{{Cite web |title=Windows intentionally weak on worms, viruses - The Arizona State Press |url=https://www.statepress.com/article/2003/11/windows-intentionally-weak-on-worms-viruses |access-date=2024-06-12 |website=www.statepress.com |language=en-US}}</ref>

Furthermore, although Windows NT and its successors are designed for security (including on a network) and multi-user PCs, they were not initially designed with Internet security in mind as much, since, when it was first developed in the early 1990s, Internet use was less prevalent.<ref>{{Cite web |title=Telephones and Internet Users by Country, 1990 and 2005 |url=http://www.infoplease.com/ipa/A0883396.html |url-status=live |archive-url=https://web.archive.org/web/20090522083608/http://www.infoplease.com/ipa/A0883396.html |archive-date=May 22, 2009 |access-date=June 9, 2009 |publisher=Information Please Database}}</ref>

In a 2002 strategy memo entitled "Trustworthy computing" sent to every Microsoft employee, Bill Gates declared that security should become Microsoft's highest priority.<ref>{{Cite magazine |last=Gates |first=Bill |title=Bill Gates: Trustworthy Computing |url=https://www.wired.com/2002/01/bill-gates-trustworthy-computing/ |url-status=live |magazine=Wired |language=en-US |issn=1059-1028 |archive-url=https://web.archive.org/web/20220929082019/https://www.wired.com/2002/01/bill-gates-trustworthy-computing/ |archive-date=September 29, 2022 |access-date=2022-09-29}}</ref><ref>{{Cite web |last=Verloy |first=Filip |title=20 Years After Bill Gates' Trustworthy Computing Memo, Cybersecurity Issues Are An Even Harder Problem |url=https://nonamesecurity.com/ |url-status=live |archive-url=https://web.archive.org/web/20220929082018/https://nonamesecurity.com/ |archive-date=September 29, 2022 |access-date=2022-09-29 |website=nonamesecurity.com |language=en}}</ref>

[[Windows Vista]] introduced a privilege elevation system called [[User Account Control]].<ref>{{Cite web |last=Northrup |first=Tony |date=June 1, 2005 |title=Windows Vista Security and Data Protection Improvements |url=https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-vista/cc507844(v=technet.10) |url-status=live |archive-url=https://web.archive.org/web/20211020154204/https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-vista/cc507844(v=technet.10) |archive-date=October 20, 2021 |access-date=October 20, 2021 |website=[[Microsoft Docs]] |quote=In Windows Vista, the User Account Control (UAC) initiative introduces fundamental operating system changes to enhance the experience for the non-administrative user. |department=[[Microsoft TechNet|TechNet]]}}</ref> When logging in as a standard user, a logon session is created and a [[Token (Windows NT architecture)|token]] containing only the most basic privileges is assigned. In this way, the new logon session is incapable of making changes that would affect the entire system. When logging in as a user in the Administrators group, two separate tokens are assigned. The first token contains all privileges typically awarded to an administrator, and the second is a restricted token similar to what a standard user would receive. User applications, including the [[Windows shell]], are then started with the restricted token, resulting in a reduced privilege environment even under an Administrator account. When an application requests higher privileges or "Run as administrator" is clicked, UAC will prompt for confirmation and, if consent is given (including administrator credentials if the account requesting the elevation is not a member of the administrators group), start the process using the unrestricted token.<ref name="kennykerr2">{{Cite web |last=Kenny Kerr |date=September 29, 2006 |title=Windows Vista for Developers&nbsp;– Part 4&nbsp;– User Account Control |url=http://weblogs.asp.net/kennykerr/archive/2006/09/29/Windows-Vista-for-Developers-_1320_-Part-4-_1320_-User-Account-Control.aspx |url-status=dead |archive-url=https://web.archive.org/web/20070329071440/http://weblogs.asp.net/kennykerr/archive/2006/09/29/Windows-Vista-for-Developers-_1320_-Part-4-_1320_-User-Account-Control.aspx |archive-date=March 29, 2007 |access-date=March 15, 2007}}</ref>

Leaked documents from 2013 to 2016 codenamed [[Vault 7]] detail the capabilities of the [[Central Intelligence Agency|CIA]] to perform electronic surveillance and cyber warfare,<ref>{{Cite magazine |last=Greenberg |first=Andy |date=March 7, 2017 |title=How the CIA Can Hack Your Phone, PC, and TV (Says WikiLeaks) |language=en-US |magazine=[[WIRED]] |url=https://www.wired.com/2017/03/cia-can-hack-phone-pc-tv-says-wikileaks/ |url-status=live |access-date=December 18, 2018 |archive-url=https://web.archive.org/web/20190320070844/https://www.wired.com/2017/03/cia-can-hack-phone-pc-tv-says-wikileaks/ |archive-date=March 20, 2019}}</ref> such as the ability to compromise operating systems such as Windows.<ref>{{Cite web |date=March 7, 2017 |title=Vault 7: Wikileaks reveals details of CIA's hacks of Android, iPhone Windows, Linux, MacOS, and even Samsung TVs |url=http://www.computing.co.uk/ctg/news/3006021/vault-7-wikileaks-reveals-details-of-cias-hacks-of-android-iphone-windows-linux-macos-and-even-samsung-tvs |url-status=live |archive-url=https://web.archive.org/web/20190412212526/https://www.computing.co.uk/ctg/news/3006021/vault-7-wikileaks-reveals-details-of-cias-hacks-of-android-iphone-windows-linux-macos-and-even-samsung-tvs |archive-date=April 12, 2019 |access-date=December 18, 2018 |website=[[Computing (magazine)|Computing]]}}</ref>

In August 2019, computer experts reported that the [[BlueKeep]] security vulnerability, {{CVE|2019-0708}}, that potentially affects older unpatched Windows versions via the program's [[Remote Desktop Protocol]], allowing for the possibility of [[remote code execution]], may include related flaws, collectively named ''[[DejaBlue]]'', affecting newer Windows versions (i.e., [[Windows 7]] and all recent versions) as well.<ref name="WRD-201908132">{{Cite magazine |last=Greenberg |first=Andy |date=August 13, 2019 |title=DejaBlue: New BlueKeep-Style Bugs Renew The Risk Of A Windows worm |magazine=[[Wired (magazine)|wired]] |url=https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/ |url-status=live |access-date=August 15, 2019 |archive-url=https://web.archive.org/web/20210413152701/https://www.wired.com/story/dejablue-windows-bugs-worm-rdp/ |archive-date=April 13, 2021}}</ref> In addition, experts reported a Microsoft [[security vulnerability]], {{CVE|2019-1162}}, based on [[legacy code]] involving [[Text Services Framework#ctfmon|Microsoft CTF and ctfmon (ctfmon.exe)]], that affects all [[Windows]] versions from [[Windows XP]] to the then most recent [[Windows 10]] versions; a patch to correct the flaw is available.<ref name="TP-201908142">{{Cite news |last=Seals |first=Tara |date=August 14, 2019 |title=20-Year-Old Bug in Legacy Microsoft Code Plagues All Windows Users |work=ThreatPost.com |url=https://threatpost.com/20-year-old-bug-legacy-microsoft-windows-users/147336/ |url-status=live |access-date=August 15, 2019 |archive-url=https://web.archive.org/web/20210417180352/https://threatpost.com/20-year-old-bug-legacy-microsoft-windows-users/147336/ |archive-date=April 17, 2021}}</ref>

Microsoft releases security patches through its [[Windows Update]] service approximately once a month (usually the [[Patch Tuesday|second Tuesday]] of the month), although critical updates are made available at shorter intervals when necessary.<ref>{{Cite web |last=Ryan Naraine |author-link=Ryan Naraine |date=June 8, 2005 |title=Microsoft's Security Response Center: How Little Patches Are Made |url=http://www.eweek.com/c/a/Windows/Microsofts-Security-Response-Center-How-Little-Patches-Are-Made/ |access-date=January 3, 2011 |website=[[eWeek]] |publisher=Ziff Davis Enterprise}}</ref> Versions subsequent to Windows 2000 SP3 and Windows XP implemented automatic download and installation of updates, substantially increasing the number of users installing security updates.<ref>{{Cite web |last=John Foley |date=October 20, 2004 |title=Windows XP SP2 Distribution Surpasses 100 Million |url=http://www.informationweek.com/news/security/vulnerabilities/showArticle.jhtml?articleID=50900297 |url-status=live |archive-url=https://web.archive.org/web/20100527044840/http://www.informationweek.com/news/security/vulnerabilities/showArticle.jhtml?articleID=50900297 |archive-date=May 27, 2010 |access-date=January 3, 2011 |website=[[InformationWeek]] |publisher=UBM TechWeb}}</ref>

Windows integrates the Windows Defender antivirus, which is seen as one of the best available.<ref>{{Cite web |title=Test antivirus software for Windows 10 – June 2022 |url=https://www.av-test.org/en/antivirus/home-windows/ |url-status=live |archive-url=https://web.archive.org/web/20220929082019/https://www.av-test.org/en/antivirus/home-windows/ |archive-date=September 29, 2022 |access-date=2022-09-29 |website=www.av-test.org |language=en-US}}</ref> Windows also implements [[Secure Boot]], [[Control-flow integrity|Control Flow Guard]], ransomware protection, [[BitLocker]] disk encryption, a firewall, and Windows SmartScreen.

In July 2024, Microsoft signalled an intention to limit kernel access and improve overall security, following a highly publicised [[2024 CrowdStrike-related IT outages|CrowdStrike update]] that caused 8.5 million Windows PCs to crash.<ref name="CrowdStrike9to5">{{cite web |last1=Christoffel |first1=Ryan |title=Microsoft starts campaign to make Windows security more like Mac post-CrowdStrike |url=https://9to5mac.com/2024/07/26/microsoft-starts-campaign-to-make-windows-security-more-like-mac-post-crowdstrike/ |website=9to5Mac |access-date=July 27, 2024 |date=July 26, 2024}}</ref> Part of that initiative is to rewrite parts of Windows in [[Rust (programming language)|Rust]], a [[memory-safe]] language.<ref>{{Cite news |last=Warren |first=Tom |date=November 19, 2024 |title=Microsoft's new Windows Resiliency Initiative aims to avoid another CrowdStrike incident |url=https://www.theverge.com/2024/11/19/24299873/microsoft-windows-resiliency-initiative-crowdstrike-incident |access-date=November 19, 2024 |work=[[The Verge]] |quote=...and Microsoft is making changes to Windows, too. It's 'gradually moving functionality from C++ implementation to Rust' in Windows, to help further improve the security of the OS.}}</ref>

=== File permissions ===
All Windows versions from Windows NT 3 have been based on a file system permission system referred to as [[AGDLP]] (Accounts, Global, Domain Local, Permissions) in which file permissions are applied to the file/folder in the form of a 'local group' which then has other 'global groups' as members. These global groups then hold other groups or users depending on different Windows versions used. This system varies from other vendor products such as [[Linux]] and [[NetWare]] due to the 'static' allocation of permission being applied directly to the file or folder. However using this process of AGLP/AGDLP/AGUDLP allows a small number of static permissions to be applied and allows for easy changes to the account groups without reapplying the file permissions on the files and folders.{{Citation needed|date=March 2025}}

== Alternative implementations ==
<!--Please do not put generic IBM PC emulators here. This section is only meant for programs that implement the Windows API. -->

Owing to the operating system's popularity, a number of applications have been released that aim to provide compatibility with Windows applications, either as a [[compatibility layer]] for another operating system, or as a standalone system that can run software written for Windows out of the box. These include:
* [[Wine (software)|Wine]] – a [[free and open-source]] implementation of the [[Windows API]], allowing one to run many Windows applications on x86-based platforms, including [[UNIX]], [[Linux]] and [[macOS]]. Wine developers refer to it as a "compatibility layer"<ref>{{Cite web |title=Wine |url=http://www.winehq.org/ |url-status=dead |archive-url=https://web.archive.org/web/20140404215516/http://www.winehq.org/ |archive-date=April 4, 2014 |access-date=April 5, 2014 |publisher=Winehq.org}}</ref> and use Windows-style APIs to emulate Windows environment.
** [[CrossOver (software)|CrossOver]] – a Wine package with licensed fonts. Its developers are regular contributors to Wine.
** [[Proton (software)|Proton]] – A fork of Wine by Valve to run Windows games on Linux and other Unix-like OS.
* [[ReactOS]] – an open-source OS intended to run the same software as Windows, originally designed to simulate Windows NT 4.0, later aiming at Windows 7 compatibility. It has been in the [[development stage]] since 1996.
*<!--The following entry is added per [[RetroWikipedia:Articles for deletion/Freedows OS (2nd nomination)]]-->'''Freedows OS'''&nbsp;– an open-source attempt at creating a Windows clone for x86 platforms, intended to be released under the [[GNU General Public License]]. Started in 1996 by Reece K. Sellin, the project was never completed, getting only to the stage of design discussions which featured a number of novel concepts until it was suspended in 2002.<ref>{{cite web |title=A Student's Dream of Creating A New Operating System Encounters Problems |url=http://chronicle.com/article/A-Students-Dream-of-Creati/103396/ |work=[[The Chronicle of Higher Education]] |date=18 September 1998 |accessdate=17 May 2013}}</ref><ref>{{cite web |url=http://www.advogato.org/person/chipx86/diary.html?start=134 |title=Older blog entries for chipx86 |work=Advogato.org |publisher=Advogato |date=27 June 2002 |accessdate=17 May 2013 |archive-date=May 20, 2013 |archive-url=https://web.archive.org/web/20130520072808/http://www.advogato.org/person/chipx86/diary.html?start=134 |url-status=dead }}</ref><ref>{{cite web|url=http://features.slashdot.org/story/98/08/31/2231220/freedows-splits |title=Freedows splits |work=[[Slashdot]] |publisher=[[Dice Holdings]] |date=31 August 1998 |accessdate=17 May 2013}}</ref>

== See also ==
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* [[Wintel]]
{{colend}}
{{clear}}

== References ==
{{Reflist}}

== External links ==
{{Sister project links |auto=1|display=Microsoft Windows}}
* {{Official website|windows.com}}
* [https://blogs.windows.com/ Official Windows Blog] {{Webarchive|url=https://web.archive.org/web/20170115201731/https://blogs.windows.com/ |date=January 15, 2017 }}
* [https://msdn.microsoft.com/ Microsoft Developer Network] {{Webarchive|url=https://web.archive.org/web/20090107142701/http://msdn.microsoft.com/. |date=January 7, 2009 }}
* [https://developer.microsoft.com/en-us/windows/ Windows Developer Center] {{Webarchive|url=https://web.archive.org/web/20161216202829/https://developer.microsoft.com/en-us/windows |date=December 16, 2016 }}
* [https://web.archive.org/web/20070202222901/http://www.microsoft.com/windows/WinHistoryIntro.mspx Microsoft Windows History Timeline]
* [https://www.informit.com/articles/article.aspx?p=1358665&rll=1 Pearson Education, InformIT] {{Webarchive|url=https://web.archive.org/web/20210628080123/https://www.informit.com/articles/article.aspx?p=1358665&rll=1 |date=June 28, 2021 }}&nbsp;– History of Microsoft Windows
* [https://www.microsoft.com/en-us/enterprise Microsoft Business Software Solutions] {{Webarchive|url=https://web.archive.org/web/20191205181024/https://www.microsoft.com/en-us/enterprise/ |date=December 5, 2019 }}
* [https://docs.microsoft.com/en-us/windows/release-information/ Windows 10 release Information] {{Webarchive|url=https://web.archive.org/web/20190507061309/https://docs.microsoft.com/en-us/windows/release-information/ |date=May 7, 2019 }}

{{Microsoft Windows family}}
{{Microsoft operating systems}}
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{{Microsoft Windows components}}
{{Operating system}}

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[[Category:Microsoft Windows| ]]
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