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92-522: The term virtual machine probably originated with the M44/44X project, from which it was later appropriated by the CP-40 team to replace their earlier term pseudo machine . Unlike CP-40 and later CP/CMS control programs, M44/44X did not implement a complete simulation of the underlying hardware (i.e. full virtualization ). CP-40 project leader Robert Creasy observed: The M44/44X "was about as much of

184-464: A high-level programming language (compared to the low-level ISA abstraction of the system VM). Process VMs are implemented using an interpreter ; performance comparable to compiled programming languages can be achieved by the use of just-in-time compilation . This type of VM has become popular with the Java programming language , which is implemented using the Java virtual machine . Other examples include

276-683: A virtual machine ( VM ) is the virtualization or emulation of a computer system . Virtual machines are based on computer architectures and provide the functionality of a physical computer. Their implementations may involve specialized hardware, software, or a combination of the two. Virtual machines differ and are organized by their function, shown here: Some virtual machine emulators, such as QEMU and video game console emulators , are designed to also emulate (or "virtually imitate") different system architectures, thus allowing execution of software applications and operating systems written for another CPU or architecture. OS-level virtualization allows

368-729: 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 has been built into Windows since Windows 3.0. The language for both

460-550: 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

552-508: 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

644-595: 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

736-478: A nested guest virtual machine does not need to be homogeneous with its host virtual machine; for example, application virtualization can be deployed within a virtual machine created by using hardware virtualization . Nested virtualization becomes more necessary as widespread operating systems gain built-in hypervisor functionality, which in a virtualized environment can be used only if the surrounding hypervisor supports nested virtualization; for example, Windows 7

828-400: 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

920-431: A normal application inside a host OS and supports a single process. It is created when that process is started and destroyed when it exits. Its purpose is to provide a platform -independent programming environment that abstracts away details of the underlying hardware or operating system and allows a program to execute in the same way on any platform. A process VM provides a high-level abstraction – that of

1012-831: A particular architecture does not provide hardware support required for nested virtualization, various software techniques are employed to enable it. Over time, more architectures gain required hardware support; for example, since the Haswell microarchitecture (announced in 2013), Intel started to include VMCS shadowing as a technology that accelerates nested virtualization. Microsoft Windows 24H2 (10.0.26100.2454) (November 21, 2024 ; 7 days ago  ( 2024-11-21 ) ) [±] 23H2 (10.0.22635.4515) (November 22, 2024 ; 6 days ago  ( 2024-11-22 ) ) [±] 24H2 (10.0.26120.2415) (November 22, 2024 ; 6 days ago  ( 2024-11-22 ) ) [±] Microsoft Windows

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1104-665: A popular approach to implementing early microcomputer software, including Tiny BASIC and adventure games, from one-off implementations such as Pyramid 2000 to a general-purpose engine like Infocom 's z-machine , which Graham Nelson argues is "possibly the most portable virtual machine ever created". Significant advances occurred in the implementation of Smalltalk -80, particularly the Deutsch/Schiffmann implementation which pushed just-in-time (JIT) compilation forward as an implementation approach that uses process virtual machine. Later notable Smalltalk VMs were VisualWorks ,

1196-563: 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

1288-506: 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

1380-460: A special version with integrated peer-to-peer networking features and a version number of 3.11, 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

1472-529: 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

1564-451: A specific programming language, but are embedded in an existing language; typically such a system provides bindings for several languages (e.g., C and Fortran ). Examples are Parallel Virtual Machine (PVM) and Message Passing Interface (MPI). Both system virtual machines and process virtual machines date to the 1960s and remain areas of active development. System virtual machines grew out of time-sharing , as notably implemented in

1656-416: 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. 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,

1748-595: A system virtual machine can be considered a generalization of the concept of virtual memory that historically preceded it. IBM's CP/CMS , the first systems to allow full virtualization , implemented time sharing by providing each user with a single-user operating system, the Conversational Monitor System (CMS). Unlike virtual memory, a system virtual machine entitled the user to write privileged instructions in their code. This approach had certain advantages, such as adding input/output devices not allowed by

1840-581: A virtual machine system as CTSS – which is to say that it was close enough to a virtual machine system to show that 'close enough' did not count. I never heard a more eloquent argument for virtual machines than from Dave Sayre." M44/44X "implanted the idea that the virtual machine concept is not necessarily less efficient than more conventional approaches" – a core assumption in the CP/CMS architecture, and one that ultimately proved very successful. Citations Virtual machine In computing ,

1932-549: Is a product line of proprietary graphical operating systems developed and marketed by Microsoft . It is grouped into families and sub-families that cater to particular sectors of the computing industry – Windows (unqualified) for a consumer or corporate workstation , Windows Server for a server and Windows IoT for an embedded system . Windows is sold as either a consumer retail product or licensed to third-party hardware manufacturers who sell products bundled with Windows. The first version of Windows, Windows 1.0 ,

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2024-493: Is also used to implement the "guest" environments, and applications running in a given "guest" environment view it as a stand-alone system. The pioneer implementation was FreeBSD jails ; other examples include Docker , Solaris Containers , OpenVZ , Linux-VServer , LXC , AIX Workload Partitions , Parallels Virtuozzo Containers, and iCore Virtual Accounts. A snapshot is a state of a virtual machine, and generally its storage devices, at an exact point in time. A snapshot enables

2116-435: 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

2208-460: Is an example of such snapshots. Restoring a snapshot consists of discarding or disregarding all overlay layers that are added after that snapshot, and directing all new changes to a new overlay. The snapshots described above can be moved to another host machine with its own hypervisor; when the VM is temporarily stopped, snapshotted, moved, and then resumed on the new host, this is known as migration. If

2300-450: 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

2392-541: Is capable of running Windows XP applications inside a built-in virtual machine. Furthermore, moving already existing virtualized environments into a cloud, following the Infrastructure as a Service (IaaS) approach, is much more complicated if the destination IaaS platform does not support nested virtualization. The way nested virtualization can be implemented on a particular computer architecture depends on supported hardware-assisted virtualization capabilities. If

2484-523: 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. By May 2017, 90 percent of its engineering team

2576-573: Is the most popular desktop operating system in the world, with a 70% market share as of March 2023 , according to StatCounter ; however when including mobile OS es, it is not the most used, in favor of Android . As of today, the most recent version of Windows is Windows 11 for consumer PCs and 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 ). As of today,

2668-447: 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

2760-609: The CP-40 and SIMMON , which used full virtualization , and were early examples of hypervisors . The first widely available virtual machine architecture was the CP-67 /CMS (see History of CP/CMS for details). An important distinction was between using multiple virtual machines on one host system for time-sharing, as in M44/44X and CP-40, and using one virtual machine on a host system for prototyping, as in SIMMON. Emulators , with hardware emulation of earlier systems for compatibility, date back to

2852-565: The Compatible Time-Sharing System (CTSS). Time-sharing allowed multiple users to use a computer concurrently : each program appeared to have full access to the machine, but only one program was executed at the time, with the system switching between programs in time slices, saving and restoring state each time. This evolved into virtual machines, notably via IBM's research systems: the M44/44X , which used partial virtualization , and

IBM M44/44X - Misplaced Pages Continue

2944-542: The IBM System/360 in 1963, while the software emulation (then-called "simulation") predates it. Process virtual machines arose originally as abstract platforms for an intermediate language used as the intermediate representation of a program by a compiler ; early examples date to around 1964 with the META II compiler-writing system using it for both syntax description and target code generation. A notable 1966 example

3036-533: The Parrot virtual machine and the .NET Framework , which runs on a VM called the Common Language Runtime . All of them can serve as an abstraction layer for any computer language. A special case of process VMs are systems that abstract over the communication mechanisms of a (potentially heterogeneous) computer cluster . Such a VM does not consist of a single process, but one process per physical machine in

3128-572: The Squeak Virtual Machine , and Strongtalk . A related language that produced a lot of virtual machine innovation was the Self programming language, which pioneered adaptive optimization and generational garbage collection . These techniques proved commercially successful in 1999 in the HotSpot Java virtual machine. Other innovations include a register-based virtual machine, to better match

3220-585: 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),

3312-950: 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 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. On September 14, 2000, Microsoft released Windows Me (Millennium Edition),

3404-494: 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

3496-568: 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

3588-448: 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

3680-446: 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 ,

3772-402: The 'host', and the virtual machine emulated on that machine is generally referred to as the 'guest'. A host can emulate several guests, each of which can emulate different operating systems and hardware platforms. The desire to run multiple operating systems was the initial motive for virtual machines, so as to allow time-sharing among several single-tasking operating systems. In some respects,

IBM M44/44X - Misplaced Pages Continue

3864-726: 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

3956-589: 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. 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

4048-632: The IBM CP-40 and CP-67 , predecessors of the VM family. Examples outside the mainframe field include Parallels Workstation , Parallels Desktop for Mac , VirtualBox , Virtual Iron , Oracle VM , Virtual PC , Virtual Server , Hyper-V , VMware Fusion , VMware Workstation , VMware Server (discontinued, formerly called GSX Server), VMware ESXi , QEMU , Adeos , Mac-on-Linux, Win4BSD, Win4Lin Pro , and Egenera vBlade technology. In hardware-assisted virtualization,

4140-445: The VM continues operation from the last-known coherent state, rather than the current state, based on whatever materials the backup server was last provided with. Nested virtualization refers to the ability of running a virtual machine within another, having this general concept extendable to an arbitrary depth. In other words, nested virtualization refers to running one or more hypervisors inside another hypervisor. The nature of

4232-457: The VM for a location on its physical disk are transparently translated into an operation on the corresponding file. Once such a translation layer is present, however, it is possible to intercept the operations and send them to different files, depending on various criteria. Every time a snapshot is taken, a new file is created, and used as an overlay for its predecessors. New data is written to the topmost overlay; reading existing data, however, needs

4324-575: The Windows NT family still ran on IA-32 up to Windows 10 (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,

4416-430: 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

4508-616: The Xbox 360's system is backwards compatible with the original Xbox. 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. This system was used up until 2017 once the system could not keep up with the size of Windows. Microsoft had begun to integrate Git into Team Foundation Server in 2013, but Windows (and Office) continued to rely on Source Depot. The Windows code

4600-522: 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

4692-452: 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

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4784-437: The application, a home networking system called HomeGroup , and performance improvements. 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

4876-401: The cluster. They are designed to ease the task of programming concurrent applications by letting the programmer focus on algorithms rather than the communication mechanisms provided by the interconnect and the OS. They do not hide the fact that communication takes place, and as such do not attempt to present the cluster as a single machine. Unlike other process VMs, these systems do not provide

4968-409: 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

5060-411: The developmental stage, so it runs inside a sandbox . Virtual machines have other advantages for operating system development and may include improved debugging access and faster reboots. Multiple VMs running their own guest operating system are frequently engaged for server consolidation. A process VM, sometimes called an application virtual machine , or Managed Runtime Environment (MRE), runs as

5152-516: 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

5244-924: The hardware provides architectural support that facilitates building a virtual machine monitor and allows guest OSes to be run in isolation. Hardware-assisted virtualization was first introduced on the IBM System/370 in 1972, for use with VM/370 , the first virtual machine operating system offered by IBM as an official product. In 2005 and 2006, Intel and AMD provided additional hardware to support virtualization. Sun Microsystems (now Oracle Corporation ) added similar features in their UltraSPARC T-Series processors in 2005. Examples of virtualization platforms adapted to such hardware include KVM , VMware Workstation , VMware Fusion , Hyper-V , Windows Virtual PC , Xen , Parallels Desktop for Mac , Oracle VM Server for SPARC , VirtualBox and Parallels Workstation . In 2006, first-generation 32- and 64-bit x86 hardware support

5336-436: 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. Windows NT included support for several platforms before

5428-505: 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

5520-433: 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

5612-416: The older snapshots are kept in sync regularly, this operation can be quite fast, and allow the VM to provide uninterrupted service while its prior physical host is, for example, taken down for physical maintenance. Similar to the migration mechanism described above, failover allows the VM to continue operations if the host fails. Generally it occurs if the migration has stopped working. However, in this case,

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5704-622: The only active top-level family is Windows NT . The first version, Windows NT 3.1 , was intended for 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. These top-level Windows families are no longer actively developed: The term Windows collectively describes any or all of several generations of Microsoft operating system products. These products are generally categorized as follows: The history of Windows dates back to 1981 when Microsoft started work on

5796-486: The overlay hierarchy to be scanned, resulting in accessing the most recent version. Thus, the entire stack of snapshots is virtually a single coherent disk; in that sense, creating snapshots works similarly to the incremental backup technique. Other components of a virtual machine can also be included in a snapshot, such as the contents of its random-access memory (RAM), BIOS settings, or its configuration settings. " Save state " feature in video game console emulators

5888-403: 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 NT was the first Windows operating system based on a hybrid kernel . The hybrid kernel

5980-489: The removal of the Start menu . 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

6072-421: The resources of a computer to be partitioned via the kernel . The terms are not universally interchangeable. A "virtual machine" was originally defined by Popek and Goldberg as "an efficient, isolated duplicate of a real computer machine." Current use includes virtual machines that have no direct correspondence to any real hardware. The physical, "real-world" hardware running the VM is generally referred to as

6164-751: 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

6256-440: The same computer (e.g., Windows , Linux , or prior versions of an operating system) to support future software. The use of virtual machines to support separate guest operating systems is popular in regard to embedded systems . A typical use would be to run a real-time operating system simultaneously with a preferred complex operating system, such as Linux or Windows. Another use would be for novel and unproven software still in

6348-453: The same physical page by a technique termed kernel same-page merging (KSM). This is especially useful for read-only pages, such as those holding code segments, which is the case for multiple virtual machines running the same or similar software, software libraries, web servers, middleware components, etc. The guest operating systems do not need to be compliant with the host hardware, thus making it possible to run different operating systems on

6440-420: The same time, through 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 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 3.0 , released in 1990, improved

6532-439: 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. Windows 3.1, made generally available on March 1, 1992, featured a facelift. In August 1993, Windows for Workgroups,

6624-415: The standard system. As technology evolves virtual memory for purposes of virtualization, new systems of memory overcommitment may be applied to manage memory sharing among multiple virtual machines on one computer operating system. It may be possible to share memory pages that have identical contents among multiple virtual machines that run on the same physical machine, what may result in mapping them to

6716-513: The underlying hardware, rather than a stack-based virtual machine, which is a closer match for the programming language; in 1995, this was pioneered by the Dis virtual machine for the Limbo language. In full virtualization, the virtual machine simulates enough hardware to allow an unmodified "guest" OS (one designed for the same instruction set ) to be run in isolation. This approach was pioneered in 1966 with

6808-429: The virtual machine's state at the time of the snapshot to be restored later, effectively undoing any changes that occurred afterwards. This capability is useful as a backup technique, for example, prior to performing a risky operation. Virtual machines frequently use virtual disks for their storage; in a very simple example, a 10- gigabyte hard disk drive is simulated with a 10-gigabyte flat file . Any requests by

6900-642: The virtual machine, notably in UCSD Pascal (1978); this influenced later interpreters, notably the Java virtual machine (JVM). Another early example was SNOBOL4 (1967), which was written in the SNOBOL Implementation Language (SIL), an assembly language for a virtual machine, which was then targeted to physical machines by transpiling to their native assembler via a macro assembler . Macros have since fallen out of favor, however, so this approach has been less influential. Process virtual machines were

6992-465: The worst operating systems Microsoft had ever released, and the fourth worst tech product of all time. 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

7084-407: 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. As of May 2022, Windows 11 is a free upgrade to Windows 10 users who meet the system requirements. In July 2021, Microsoft announced it will start selling subscriptions to virtualized Windows desktops as part of

7176-492: 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. 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

7268-509: Was designed as a modified microkernel , influenced by the 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 workstations and servers . Windows NT 3.5

7360-427: Was found to rarely offer performance advantages over software virtualization. In OS-level virtualization, a physical server is virtualized at the operating system level, enabling multiple isolated and secure virtualized servers to run on a single physical server. The "guest" operating system environments share the same running instance of the operating system as the host system. Thus, the same operating system kernel

7452-462: 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

7544-690: 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

7636-474: Was popularized around 1970 by Pascal , notably in the Pascal-P system (1973) and Pascal-S compiler (1975), in which it was termed p-code and the resulting machine as a p-code machine . This has been influential, and virtual machines in this sense have been often generally called p-code machines. In addition to being an intermediate language, Pascal p-code was also executed directly by an interpreter implementing

7728-458: Was released in April 2003. It was followed in December 2005, by Windows Server 2003 R2. After a lengthy development process , Windows Vista was released on November 30, 2006, for volume licensing and January 30, 2007, for 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

7820-609: 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 ,

7912-671: 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

8004-505: Was released on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs). The name "Windows" is a reference to the windowing system in GUIs. 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 CE/Embedded Compact . Windows

8096-401: 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

8188-540: Was the O-code machine , a virtual machine that executes O-code (object code) emitted by the front end of the BCPL compiler. This abstraction allowed the compiler to be easily ported to a new architecture by implementing a new back end that took the existing O-code and compiled it to machine code for the underlying physical machine. The Euler language used a similar design, with the intermediate language named P (portable). This

8280-582: 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 , 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. Windows CE (officially known as Windows Embedded Compact ),

8372-551: 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

8464-420: Was using Git, in about 8500 commits and 1760 Windows builds per day. 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. On June 24, 2021, Windows 11

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