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 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". It was announced in November 1983 (after the
Apple Lisa, but before the
Macintosh) under the name "Windows", but
Windows 1.0 was not released until November 1985. Windows 1.0 was to compete with
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
Calculator, Calendar,
Cardfile,
Clipboard Viewer, Clock,
Control Panel,
Notepad,
Paint,
Reversi,
Terminal and
Write. Windows 1.0 does not allow overlapping windows. Instead, all windows are
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.
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. Windows 2.03 changed the OS from tiled windows to overlapping windows. The result of this change led to
Apple Computer filing a suit against Microsoft alleging infringement on Apple's copyrights (eventually settled in court in Microsoft's favor in 1993). Windows 2.0 also introduced more sophisticated
keyboard shortcuts 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
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. 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. 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 drivers (timer, graphics, printer, mouse, keyboard 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 virtual memory scheme, which allowed it to run applications larger than available memory: code segments and
resources were 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 Windows 3.0, released in 1990, improved the design, mostly because of
virtual memory and loadable virtual device drivers (
VxDs) that allow Windows to share arbitrary devices between multi-tasked DOS applications. 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 into
assembly. Windows 3.0 was the first version of Windows to achieve broad commercial success, selling 2 million copies in the first six months. 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
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. Windows 3.2, released in 1994, is an updated version of the Chinese version of Windows 3.1. The update was limited to this language version, as it fixed only issues related to the complex writing system of the Chinese language. 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.
Windows 9x 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 applications,
plug and play hardware,
preemptive multitasking,
long file names of up to 255 characters, and provided increased stability over its predecessors. Windows 95 also introduced a redesigned,
object oriented user interface, replacing the previous
Program Manager with the
Start menu,
taskbar, and
Windows Explorer 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." 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. Mainstream support for Windows 95 ended on December 31, 2000, and extended support for Windows 95 ended on December 31, 2001. 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 devices, support for
ACPI,
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 June 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. 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), 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 networking tools. 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.
Windows NT Version history Early versions (Windows NT 3.1/3.5/3.51/4.0/2000) 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,
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 port of the
Windows API known as Win32 instead of those of OS/2. Win32 maintained a similar structure to the Windows
APIs (allowing existing Windows applications to easily be
ported to the platform), but also supported the capabilities of the existing NT
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.
Windows XP 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"
Windows Explorer), streamlined multimedia and networking features,
Internet Explorer 6, integration with Microsoft's
.NET Passport services, a "
compatibility mode" to help provide
backwards compatibility with software designed for previous versions of Windows, and
Remote Assistance functionality. At retail, Windows XP was marketed in two main
editions: the "Home" edition was targeted towards consumers, while the "Professional" edition was targeted towards business environments and
power users, and included additional security and networking features. Home and Professional were later accompanied by the "
Media Center" edition (designed for
home theater PCs, with an emphasis on support for
DVD playback,
TV tuner cards,
DVR functionality, and remote controls), and the "Tablet PC" edition (designed for mobile devices meeting its
specifications for a
tablet computer, with support for
stylus pen input and additional pen-enabled applications). Mainstream support for Windows XP ended on April 14, 2009. Extended support ended on April 8, 2014. 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.
Windows Vista After a lengthy
development process,
Windows Vista was released only for volume licensing on November 30, 2006, and finally, on January 30, 2007, it was officially released to everyone, including consumers. It contained a number of
new features, from a redesigned shell and user interface to significant
technical changes, with a particular focus on
security features. It was available in a number of
different editions, and has been subject to
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 On July 22, 2009,
Windows 7 and
Windows Server 2008 R2 were released to manufacturing (RTM) and were officially released, including for the public, 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. Windows 7 has
multi-touch support, a redesigned
Windows shell with an updated
taskbar with revealable
jump lists that contain shortcuts to files frequently used with specific applications and shortcuts to tasks within the application, a home networking system called
HomeGroup, and performance improvements.
Windows 8 and 8.1 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 with optimizations for
touch-based devices such as
tablets and all-in-one PCs. These changes include the
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
apps which are designed primarily for use on touch-based devices. The new Windows version required a minimum resolution of 1024×768 pixels, effectively making it unfit for
netbooks with 800×600-pixel screens. Other changes include increased integration with
cloud services and other online platforms (such as
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, and a new keyboard shortcut for
screenshots. An update to Windows 8, called
Windows 8.1, 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 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). 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. 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. On April 27, 2023, Microsoft announced that version 22H2 would be the last of Windows 10.
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. Windows 11 is a free upgrade to Windows 10 users who meet the system requirements.
Windows 365 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 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. 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
Apple App Store. Microsoft announced Windows 365 availability to business and enterprise customers on August 2, 2021.
Multilingual support 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 Editors, 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 Packs (LIPs) are redistributable and may be downloaded from Microsoft's Download Center and installed for any edition of Windows (XP or later)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 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 Windows CE Windows CE (officially known as
Windows Embedded Compact), is an edition of Windows that runs on
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
OEMs 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 CE 6.0 R3 and
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 Xbox OS is an unofficial name given to the version of Windows that runs on
Xbox consoles. 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. 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. 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". Xbox One and
Xbox Series operating systems also allow limited (due to licensing restrictions and testing resources) backward compatibility with previous generation hardware, and the Xbox 360's system is backwards compatible with the original Xbox. == Version control system ==