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Microsoft Windows Microsoft Windows “Windows” redirects here. For the part of a building, see • Windows NT: Started as a family of operating sys- window. For other uses, see Windows (disambiguation). tem with Windows NT 3.1, an operating system for server computers and workstations. It now consists Microsoft Windows (or simply Windows) is a metafam- of three operating system subfamilies that are re- leased almost at the same time and share the same ily of graphical operating systems developed, marketed, and sold by Microsoft. It consists of several families kernel of operating systems, each of which cater to a cer- • Windows: The operating system for main- tain sector of the computing industry. Active Win- stream personal computers. The latest version dows families include Windows NT, Windows Embed- is Windows 10. It is almost impossible for ded and Windows Phone; these may encompass subfam- someone unfamiliar with the subject to iden- ilies, e.g. Windows Embedded Compact (Windows CE) tify the members of this family by name be- or Windows Server. Defunct Windows families include cause they do not adhere to any specific rule; Windows 9x and Windows Mobile. e.g. Windows Vista, Windows 7, Windows Microsoft introduced an operating environment named 8/8.1 and Windows RT are members of this Windows on November 20, 1985, as a graphical operating family but Windows 3.1 is not. The main com- system shell for MS-DOS in response to the growing in- petitor of this family is OS X by Apple Inc. terest in graphical user interfaces (GUIs).[4] Microsoft (c.f. Usage share of operating systems § Mar- Windows came to dominate the world’s personal com- ket share by category) puter market with over 90% market share, overtaking • Windows Server: The operating system for Mac OS, which had been introduced in 1984. However, server computers. The latest version is since 2012, thanks to the massive growth of smartphones, Windows Server 2012 R2. Unlike its clients Windows sells less than Android, which became the most sibling, it has adopted a strong naming scheme. popular operating system in 2014, when counting all of The main competitor of this family is Linux. the computing platforms each operating system runs on; (c.f. Usage share of operating systems § Mar- in 2014, the number of Windows devices sold were less ket share by category) than 25% of Android devices sold. However, compar- isons across different markets are not fully relevant; and • Windows PE: A lightweight version of its Win- for personal computers, Windows is still the most popular dows sibling meant to operate as a live op- operating system. erating system, used for installing Windows on bare-metal computers (especially on many As of July 2015, the most recent version of Windows for computers at once), recovery or troubleshoot- personal computers, tablets and smartphones is Windows ing purposes. The latest version is Windows 10. The most recent versions for server computers and PE 5.1. embedded devices are respectively Windows Server 2012 R2 and Windows Embedded 8. A specialized version of • [5] Windows Phone: An operating system sold only to Windows runs on the Xbox One game console. manufacturers of smartphones. The first version was The next server version of Windows is Windows Server Windows Phone 7. The latest version is Windows 2016, which is expected to be released in early 2016. Phone 8.1. The main competitor of this family is Android by Google. (c.f. Usage share of operating systems § Market share by category) 1 Genealogy • Windows Embedded: Initially, Microsoft devel- oped Windows CE as a general-purpose operat- 1.1 By marketing role ing system for every device that was too resource- limited to be called a full-fledged computer. Even- Microsoft, the developer of Windows, has registered sev- tually, however, Windows CE was renamed Win- eral trademarks each of which denote a family of Win- dows Embedded Compact and was folded under dows operating systems that target a specific sector of the Windows Compact trademark which also consists computing industry. As of 2014, the following Windows of Windows Embedded Industry, Windows Embed- families are being actively developed: ded Professional, Windows Embedded Standard, 1 2 2 VERSION HISTORY Windows Embedded Handheld and Windows Em- of Windows 1.0 is a program known as the MS-DOS bedded Automotive.[6] Executive. Components included Calculator, Calen- dar, Cardfile, Clipboard viewer, Clock, Control Panel, The following Windows families are no longer being de- Notepad, Paint, Reversi, Terminal and Write. Windows veloped: 1.0 does not allow overlapping windows. Instead all win- dows are tiled. Only modal dialog boxes may appear over • Windows 9x: An operating system that targeted other windows. consumers market. Discontinued because of subop- Windows 2.0 was released in December 1987, and was timal performance. (PC World called its last ver- more popular than its predecessor. It features several im- sion, Windows ME, one of the worst products of [7] provements to the user interface and memory manage- all times.) Microsoft now caters to the consumers ment. Windows 2.03 changed the OS from tiled windows market with Windows NT. to overlapping windows. The result of this change led • Windows Mobile: The predecessor to Windows to Apple Computer filing a suit against Microsoft alleg- [9][10] Phone, it was a mobile phone operating system. The ing infringement on Apple’s copyrights. Windows first version was called Pocket PC 2000; the third 2.0 also introduced more sophisticated keyboard short- version, Windows Mobile 2003 is the first version cuts and could make use of expanded memory. to adopt the Windows Mobile trademark. The last Windows 2.1 was released in two different versions: version is Windows Mobile 6.5. Windows/286 and Windows/386. Windows/386 uses the virtual 8086 mode of the Intel 80386 to multitask sev- eral DOS programs and the paged memory model to em- 2 Version history ulate expanded memory using available extended mem- ory. Windows/286, in spite of its name, runs on both Intel Main article: History of Microsoft Windows 8086 and Intel 80286 processors. It runs in real mode but See also: List of Microsoft Windows versions can make use of the high memory area. In addition to full Windows-packages, there were The term Windows collectively describes any or all of sev- runtime-only versions that shipped with early Windows eral generations of Microsoft operating system products. software from third parties and made it possible to run These products are generally categorized as follows: their Windows software on MS-DOS and without the full Windows feature set. The early versions of Windows are often thought of 2.1 Early versions as graphical shells, mostly because they ran on top of MS-DOS and use it for file system services.[11] How- Main articles: Windows 1.0, Windows 2.0 and Windows ever, even the earliest Windows versions already assumed 2.1x many typical operating system functions; notably, hav- The history of Windows dates back to September 1981, ing their own executable file format and providing their own device drivers (timer, graphics, printer, mouse, key- board and sound). Unlike MS-DOS, Windows allowed users to execute multiple graphical applications at the same time, through cooperative multitasking. Windows implemented an elaborate, segment-based, software vir- tual memory scheme, which allows it to run applica- tions larger than available memory: code segments and 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 1.0, the first version, released in 1985 2.2 Windows 3.x when Chase Bishop, a computer scientist, designed the first model of an electronic device and project Interface Main articles: Windows 3.0 and Windows 3.1x Manager was started. It was announced in November Windows 3.0, released in 1990, improved the design, 1983 (after the Apple Lisa, but before the Macintosh) mostly because of virtual memory and loadable virtual under the name “Windows”, but Windows 1.0 was not device drivers (VxDs) that allow Windows to share ar- released until November 1985.[8] Windows 1.0 was to bitrary devices between multi-tasked DOS applications. compete with Apple's operating system, but achieved Windows 3.0 applications can run in protected mode, little popularity. Windows 1.0 is not a complete op- which gives them access to several megabytes of memory erating system; rather, it extends MS-DOS. The shell without the obligation to participate in the software vir- 2.4 Windows NT 3 puter desktops around the world.”[17] 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.[18] Mainstream support for Windows 95 ended on December 31, 2000, and extended support for Windows 95 ended on December 31, 2001.[19] Windows 95 was followed up with the release of Windows 98 on June 25, 1998, which introduced the Windows Driver Model, support for USB composite de- vices, support for ACPI, hibernation, and support for multi-monitor configurations. Windows 98 also included integration with Internet Explorer 4 through Active Desk- Windows 3.0, released in 1990 top and other aspects of the Windows Desktop Update (a series of enhancements to the Explorer shell which were also made available for Windows 95). In May 1999, Mi- tual memory scheme. They run inside the same address crosoft released Windows 98 Second Edition, an updated space, where the segmented memory provides a degree of version of Windows 98.
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