Windows 8
Windows 8 is a version of Microsoft Windows (an operating system developed by Microsoft) for use on personal computers, including home and business desktops, laptops, tablets, and home theater PCs. Development of Windows 8 started before the release of its predecessor, Windows 7, in 2009. It was announced at CES 2011, and followed by the release of three pre-release versions from September 2011 to May 2012. The operating system was released to manufacturing on August 1, 2012, and was released for general availability on October 26, 2012.
Windows 8 introduces significant changes to the operating system's platform, primarily focused towards improving its user experience on mobile devices such as tablets to better compete with other mobile operating systems like Android and Apple's iOS. Windows 8 features a new touch user interface and shell based on Microsoft's "Metro" design language, featuring a new Start screen with a grid of dynamically updating tiles that represent applications. The Start screen replaces the "Start menu" of earlier Windows versions. There is a new app platform with an emphasis on touchscreen input, and the new Windows Store to obtain and/or purchase applications to run on the operating system.
In addition, Windows 8 takes advantage of new or emerging technologies like USB 3.0, 4Kn Advanced Format, near field communications, cloud computing, and the low-power ARM architecture. It includes new security features such as built-in antivirus capabilities, a new installation process optimized for digital distribution, and support for secure boot (a UEFI feature which allows operating systems to be digitally signed to prevent malware from altering the boot process). Synchronization of certain apps and settings between multiple devices is supported.
Windows 8 was released to mixed reception. Although reaction towards its performance improvements, security enhancements, and improved support for touchscreen devices was positive, the new user interface of the operating system has been widely criticized for being potentially confusing and difficult to learn (especially when used with a keyboard and mouse instead of a touchscreen). Despite these shortcomings, 60 million Windows 8 licenses have been sold through January 2013. This includes upgrades and sales to OEMs for new PCs.
Windows 8.1 is scheduled for release in late 2013 and, according to Microsoft, will change "key aspects" of how Windows 8 is used, including the reinstatement of the Start button.
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|
| Developer | |
|---|---|
| Microsoft Corporation | |
| Website | windows.microsoft.com |
| Releases | |
| Initial release | August 1, 2012 |
| General availability |
October 26, 2012 |
| Latest stable release |
6.2 (Build 9200) (August 1, 2012) |
| Latest preview release |
6.3 (Build 9431) |
| License | Proprietary commercial software |
| Kernel type | Hybrid |
| Update method | Windows Update |
| Platform support | IA-32, x64, and ARM |
| Preceded by | Windows 7 (2009) |
| Support status | |
| |
Development history
Windows 8 development started before Windows 7 had shipped in 2009. At the Consumer Electronics Show in January 2011, Microsoft announced that the next version of Windows would add support for devices with ARM microprocessors, and showcased an early version of what would become Windows 8, NT 6.2 build 7867, running on several prototype ARM devices. Details also began to surface about a new application framework for Windows 8 codenamed "Jupiter", which would be used to make "immersive" applications using XAML (similarly to Windows Phone and Silverlight) that could be distributed via a new packaging system and a rumored app store.Three milestone releases of Windows 8 leaked to the general public. Milestone 1, Build 7850, was leaked on April 12, 2011. It was the first build where the text of a window was written centered instead of aligned to the left. It was also probably the first appearance of the Metro-style font, and its wallpaper had the text shhh... let's not leak our hard work. However, its detailed build number reveals that the build was created on September 22, 2010. The leaked copy edition was Enterprise edition. The OS still reads as "Windows 7". Milestone 2, Build 7955, was leaked on April 25, 2011. The traditional Blue Screen of Death (BSoD) was replaced by a new Black screen, although this was later scrapped. This build introduced a new ribbon in Windows Explorer. Build 7959, with minor changes but the first 64-bit version, was leaked on May 1, 2011. The "Windows 7" logo was temporarily replaced with text displaying "Microsoft Confidential". On June 17, 2011, build 7989 64-bit edition was leaked. It introduced a new boot screen featuring the same fish as the default Windows 7 Beta wallpaper, which was later scrapped, and the circling dots as featured in the final (although the final version comes with smaller circling dots throbber). It also had the text Welcome below them, although this was also scrapped.
On June 1, 2011, Microsoft unveiled Windows 8's new user interface as well as additional features at both Computex Taipei and the D9: All Things Digital conference in California.
The "Building Windows 8" blog launched on August 15, 2011, featuring details surrounding Windows 8's features and its development process.
Windows Store apps
Windows 8 introduces a new style of application, Windows Store apps. According to Microsoft developer Jensen Harris, these apps are to be optimized for touchscreen environments and will be more specialized than current desktop applications. Apps can run either in a full-screen mode, or be snapped to the side of a screen. Apps can provide toast notifications on screen or animate their tiles on the Start screen with dynamic content. Apps can use "contracts"; a collection of hooks to provide common functionality that can integrate with other apps, such as search and sharing. Apps can also provide integration with other services; for example, the
People app can connect to a variety of different social networks and
services (such as Facebook, Skype, and People service), while the Photos app can aggregate photos from services such as Facebook and Flickr.
Windows Store apps run within a new set of APIs known as the Windows Runtime, which supports programming languages such as C, C++, VB.NET, C#, along with HTML5 and JavaScript. Depending on the language used, apps written for Windows Runtime can be compatible with both Intel and ARM versions of Windows. Components may be compiled as Windows Runtime Components, permitting consumption by all of the Windows Runtime supported languages. To ensure stability and security, apps run within a sandboxed environment, and require permissions to access certain functionality, such as accessing the Internet or a camera.
Retail versions of Windows 8 will be able to install these apps only through the Windows Store—a namesake distribution platform which offers both apps, and listings for desktop programs certified for comparability with Windows 8. A method to sideload apps from outside the Windows Store is available to devices running Windows 8 Enerprise and joined to a domain; Windows 8 Pro and Windows RT devices that are not part of a domain can also sideload apps, but only after special product keys are obtained through volume licensing.
The term "Immersive app" had been used internally by Microsoft developers to refer to the apps prior to the first official presentation of Windows 8, after which they were referred to as "Metro-style apps" in reference to the Metro design language. The term was phased out in August 2012; a Microsoft spokesperson denied rumors that the change was related to a potential trademark issue, and stated that "Metro" was only a codename that would be replaced prior to Windows 8's release. Following these reports, the terms "Modern UI-style apps", "Windows 8-style apps" and "Windows Store apps" began to be used by various Microsoft documents and material to refer to the new apps. In an interview on September 12, 2012, Soma Somasegar (vice president of Microsoft's development software division) confirmed that "Windows Store apps" would be the official term for the apps.
The developers of both Chrome and Firefox committed to developing versions of their browsers to run in this environment; while Chrome's "Windows 8 mode" uses the existing desktop interface, Firefox's Metro version (which is currently available in development builds) uses a touch-optimized interface inspired by the Android version of Firefox.
A vertical toolbar known as the charms (accessed by swiping from the right edge of a touchscreen, or pointing the cursor at hotspots in the right corners of a screen) provides access to system and app-related functions, such as search, sharing, device management, settings, and a Start button. The traditional desktop environment for running desktop applications is accessed via a tile on the Start screen. The Start button on the taskbar has been removed in favor of the Start charm and a hotspot in the lower-left corner of the screen, which displays a large tooltip displaying a thumbnail of the Start screen. Swiping from the left edge of a touchscreen or clicking in the top-left corner of the screen allows one to switch between apps and the Desktop. Pointing the cursor in the top-left corner of the screen and moving down reveals a thumbnail list of active apps. Aside from the removal of the Start button, the desktop on Windows 8 is similar to that of Windows 7, except that the Aero Glass theme has been replaced by a flatter, solid-colored design inspired by the Metro interface.
Microsoft faced criticism (particularly from free software supporters) for mandating that devices receiving its optional certification for Windows 8 have secure boot enabled by default using a key provided by Microsoft. Concerns were raised that secure boot could prevent or hinder the use of alternate operating systems such as Linux. In response to the criticism, Microsoft developer Tony Mangefeste stated that "At the end of the day, the customer is in control of their PC. Microsoft's philosophy is to provide customers with the best experience first, and allow them to make decisions themselves."
Microsoft's certification requirements eventually revealed that UEFI firmware on x86 systems must allow users to re-configure or turn off secure boot, but that this must not be possible on ARM-based systems (Windows RT). Microsoft faced further criticism for its decision to restrict Windows RT devices by using this functionality. Tom Warren, in an article on The Verge, said that other smartphones and tablets are typically sold in a locked-down state. No mandate is made regarding the installation of third-party certificates that would enable running alternative software.
Backup and Restore, the former backup app of Windows, is deprecated. It still ships with Windows 8 and continues to work on preset schedules, but is pushed to the background and can only be accessed through a Control Panel applet called "Windows 7 File Recovery". Shadow Copy, a component of Windows Explorer that once saved previous versions of changed files, no longer protects local files and folders. It can only access previous versions of shared files stored on a Windows Server computer. The subsystem on which these components worked, however, is still available for other software to use.
The minimum system requirements for Windows 8 are slightly higher than those of Windows 7. The CPU must support the Physical Address Extension (PAE), NX bit, and SSE2. Windows Store apps require a screen resolution of 1024×768 or higher to run. They require a screen resolution of 1366×768 or higher for snap functionality. To receive certification, Microsoft requires candidate x86 systems to resume from standby in 2 seconds or less.
The 64-bit sub-edition runs on CPUs compatible with x86 8th generation (known as x86-64, or x64) or newer, and can run 32-bit and 64-bit programs. 32-bit programs and operating system are restricted to supporting only 4 gigabytes of memory while 64-bit systems can theoretically support 2048 gigabytes of memory. 64-bit operating systems require a different set of device drivers than those of 32-bit operating systems.
Windows RT, the only edition of Windows 8 for systems with ARM processors, only supports applications included with the system (such as a special version of Office 2013), supplied through Windows Update, or Windows Store apps, to ensure that the system only runs applications that are optimized for the architecture. Windows RT does not support running IA-32 or x64 applications. Windows Store apps can either support both the x86 and ARM architectures, or compiled to support a specific architecture.
Windows Store apps run within a new set of APIs known as the Windows Runtime, which supports programming languages such as C, C++, VB.NET, C#, along with HTML5 and JavaScript. Depending on the language used, apps written for Windows Runtime can be compatible with both Intel and ARM versions of Windows. Components may be compiled as Windows Runtime Components, permitting consumption by all of the Windows Runtime supported languages. To ensure stability and security, apps run within a sandboxed environment, and require permissions to access certain functionality, such as accessing the Internet or a camera.
Retail versions of Windows 8 will be able to install these apps only through the Windows Store—a namesake distribution platform which offers both apps, and listings for desktop programs certified for comparability with Windows 8. A method to sideload apps from outside the Windows Store is available to devices running Windows 8 Enerprise and joined to a domain; Windows 8 Pro and Windows RT devices that are not part of a domain can also sideload apps, but only after special product keys are obtained through volume licensing.
The term "Immersive app" had been used internally by Microsoft developers to refer to the apps prior to the first official presentation of Windows 8, after which they were referred to as "Metro-style apps" in reference to the Metro design language. The term was phased out in August 2012; a Microsoft spokesperson denied rumors that the change was related to a potential trademark issue, and stated that "Metro" was only a codename that would be replaced prior to Windows 8's release. Following these reports, the terms "Modern UI-style apps", "Windows 8-style apps" and "Windows Store apps" began to be used by various Microsoft documents and material to refer to the new apps. In an interview on September 12, 2012, Soma Somasegar (vice president of Microsoft's development software division) confirmed that "Windows Store apps" would be the official term for the apps.
Web browsers
Exceptions to the restrictions faced by Windows Store apps are given to web browsers; the user's default browser can provide a "New experience enabled" (formerly "Metro-style enabled") version that runs within the "Metro" shell like other apps. Web browser apps are distributed alongside desktop web browsers, and also have access to functionality unavailable to other apps, such as being able to permanently run in the background, use multiple background processes, and use Windows API code instead of WinRT (allowing for code to be re-used with the desktop version, while still taking advantage of WinRT features such as contracts to integrate with charms).The developers of both Chrome and Firefox committed to developing versions of their browsers to run in this environment; while Chrome's "Windows 8 mode" uses the existing desktop interface, Firefox's Metro version (which is currently available in development builds) uses a touch-optimized interface inspired by the Android version of Firefox.
Interface and desktop
Windows 8 introduces significant changes to the operating system's user interface, many of which are aimed at improving its experience on tablet computers and other touchscreen devices. The new user interface is based on Microsoft's Metro design language, and uses a Start screen similar to that of Windows Phone as the primary means of launching applications. The Start screen displays a customizable array of tiles linking to various apps and desktop programs, some of which can display constantly updated information and content through "live tiles". As a form of multi-tasking, apps can be snapped to the side of a screen. Alongside the traditional Control Panel, a new simplified and touch-optimized settings app known as "PC Settings" is used for basic configuration and user settings. It does not include many of the advanced options still accessible from the normal Control Panel.A vertical toolbar known as the charms (accessed by swiping from the right edge of a touchscreen, or pointing the cursor at hotspots in the right corners of a screen) provides access to system and app-related functions, such as search, sharing, device management, settings, and a Start button. The traditional desktop environment for running desktop applications is accessed via a tile on the Start screen. The Start button on the taskbar has been removed in favor of the Start charm and a hotspot in the lower-left corner of the screen, which displays a large tooltip displaying a thumbnail of the Start screen. Swiping from the left edge of a touchscreen or clicking in the top-left corner of the screen allows one to switch between apps and the Desktop. Pointing the cursor in the top-left corner of the screen and moving down reveals a thumbnail list of active apps. Aside from the removal of the Start button, the desktop on Windows 8 is similar to that of Windows 7, except that the Aero Glass theme has been replaced by a flatter, solid-colored design inspired by the Metro interface.
Secure boot
See also: Unified Extensible Firmware Interface#Secure boot and Hardware restrictions#Windows 8
Windows 8 supports a feature of the UEFI specification known as "Secure boot", which uses a public-key infrastructure to verify the integrity of the operating system and prevent unauthorized programs such as bootkits from infecting the device.Microsoft faced criticism (particularly from free software supporters) for mandating that devices receiving its optional certification for Windows 8 have secure boot enabled by default using a key provided by Microsoft. Concerns were raised that secure boot could prevent or hinder the use of alternate operating systems such as Linux. In response to the criticism, Microsoft developer Tony Mangefeste stated that "At the end of the day, the customer is in control of their PC. Microsoft's philosophy is to provide customers with the best experience first, and allow them to make decisions themselves."
Microsoft's certification requirements eventually revealed that UEFI firmware on x86 systems must allow users to re-configure or turn off secure boot, but that this must not be possible on ARM-based systems (Windows RT). Microsoft faced further criticism for its decision to restrict Windows RT devices by using this functionality. Tom Warren, in an article on The Verge, said that other smartphones and tablets are typically sold in a locked-down state. No mandate is made regarding the installation of third-party certificates that would enable running alternative software.
Removed features
Main article: List of features removed in Windows 8
Several notable features have been removed in Windows 8, beginning with the traditional Start menu. Support for playing DVDs has been removed from Windows Media Player due to the cost of licensing the necessary decoders (especially for devices which do not include optical disc drives at all) and the prevalence of streaming services such as Netflix. For the same reasons, Windows Media Center
will no longer be included by default on Windows 8, but the software
(which also includes support for DVD playback) can be purchased in the
"Pro Pack" (for the base version of Windows 8, which also upgrades the
system to Windows 8 Pro) or "Media Center Pack" (for Windows 8 Pro)
add-ons. Windows 8 will still support third-party DVD playback software.Backup and Restore, the former backup app of Windows, is deprecated. It still ships with Windows 8 and continues to work on preset schedules, but is pushed to the background and can only be accessed through a Control Panel applet called "Windows 7 File Recovery". Shadow Copy, a component of Windows Explorer that once saved previous versions of changed files, no longer protects local files and folders. It can only access previous versions of shared files stored on a Windows Server computer. The subsystem on which these components worked, however, is still available for other software to use.
Hardware requirements
PCs
The minimum system requirements for Windows 8 are slightly higher than those of Windows 7. The CPU must support the Physical Address Extension (PAE), NX bit, and SSE2. Windows Store apps require a screen resolution of 1024×768 or higher to run. They require a screen resolution of 1366×768 or higher for snap functionality. To receive certification, Microsoft requires candidate x86 systems to resume from standby in 2 seconds or less.
Minimum hardware requirements for Windows 8
Tablets and convertibles
Microsoft released minimum hardware requirements for new tablet and
convertible devices certified for Windows 8, and defined a convertible
form factor as a standalone device that combines the PC, display and
rechargeable power source with a mechanically attached keyboard and
pointing device in a single chassis. A convertible can be transformed
into a tablet where the attached input devices are hidden or removed
leaving the display as the only input mechanism. On March 12, 2013, Microsoft amended its certification requirements to
only require that screens on tablets have a minimum resolution of
1024×768 (down from the previous 1366×768). The amended requirement is
intended to allow "greater design flexibility" for future products.Tablets and convertibles
Hardware certification requirements for Windows tablets
Software compatibility
The three desktop editions of Windows 8 are sold in two sub-editions: 32-bit and 64-bit. The 32-bit sub-edition runs on CPUs compatible with x86 architecture 3rd generation (known as IA-32) or newer, and can run 32-bit and 16-bit applications, although 16-bit support must be enabled first. (16-bit applications are developed for CPUs compatible with x86 2nd generation, first conceived in 1978. Microsoft started moving away from this architecture since Windows 95.)The 64-bit sub-edition runs on CPUs compatible with x86 8th generation (known as x86-64, or x64) or newer, and can run 32-bit and 64-bit programs. 32-bit programs and operating system are restricted to supporting only 4 gigabytes of memory while 64-bit systems can theoretically support 2048 gigabytes of memory. 64-bit operating systems require a different set of device drivers than those of 32-bit operating systems.
Windows RT, the only edition of Windows 8 for systems with ARM processors, only supports applications included with the system (such as a special version of Office 2013), supplied through Windows Update, or Windows Store apps, to ensure that the system only runs applications that are optimized for the architecture. Windows RT does not support running IA-32 or x64 applications. Windows Store apps can either support both the x86 and ARM architectures, or compiled to support a specific architecture.
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