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The transition from Windows 7 to Windows 8 introduced a number of new features across various aspects of the operating system. Among these included a greater focus on optimizing the operating system for touchscreen-based devices (such as tablets) and cloud computing.
Apps in Windows 8 may snap to the side of a widescreen display to allow multi-tasking, forming a sidebar. In Windows 8.1, the size of this sidebar can be changed. Snapped apps may occupy half of the screen. Large screens allow up to four apps to be snapped. Upon launching an app, Windows allows the user to pick which snapped view the app should open into.
The term "Metro-style apps" referred to "Metro", a design language prominently used by Windows 8 and other recent Microsoft products. Reports surfaced that Microsoft employees were told to stop using the term due to potential trademark issues with an unspecified partner. A Microsoft spokesperson however, denied these reports and stated that "Metro-style" was merely a codename for the new application platform.
Windows 8 also introduces APIs to support near field communication (NFC) on Windows 8 devices, allowing functionality like launching URLs/applications and sharing of information between devices via NFC.
Windows Store is a digital distribution platform built into Windows 8, which in a manner similar to Apple's App Store and Google Play, allows for the distribution and purchase of apps designed for Windows 8. Developers will still be able to advertise desktop software through Windows Store as well. To ensure that they are secure and of a high quality, Windows Store will be the only means of distributing WinRT-based apps for consumer-oriented versions of Windows 8.
In Windows 8.1, Windows Store features a redesigned interface with improved app discovery and recommendations and offers automatic updates for apps.
Apps can either run in a full-screen environment, or be snapped to the side of a screen alongside another app or the desktop; snapping requires a screen resolution of 1366×768 or higher. Users can switch between apps and the desktop by clicking on the top left corner or swiping the left side of the touchscreen to invoke a sidebar that displays all currently opened Metro-style apps. The traditional desktop is accessible from a tile on the Start screen, or by launching a desktop app. The Alt-Tab shortcut cycles through all programs, regardless of type.
The interface also incorporates a taskbar on the right side of the screen known as "the charms" (lowercase), which can be accessed from any app or the desktop by sliding from the right edge of a touchscreen or compatible trackpad, moving the mouse cursor to one of the right corners of the screen, or pressing ⊞ Win+C. The charms include Search, Share, Start, Devices and Settings charms. The Start charm invokes or dismisses the Start screen. Other charms invoke context-sensitive sidebars that can be used to access app and system functionality.
In Windows 8.1, the mentioned hotspots in the upper right and the upper left corners can be disabled.
Pressing ⊞ Win+X or right-clicking on the bottom left corner of the screen opens The Quick Link menu. This menu contains shortcuts to frequently areas such as Control Panel, File Explorer, Programs and Features, Run, Search, Power Options and Task Manager. In Windows 8.1, Quick Link menu allows shutting down or restarting the device.
A number of apps are included in the standard installation of Windows 8, including Mail (an email client), People (a contact manager), Messaging (an IM client), Calendar (a calendaring app), Photos (an image viewer), Music (an audio player), Video (a video player), Camera (a webcam or digital camera client), SkyDrive, Reader (an e-book reader), and six other apps that expose Bing services (Search, News, Finance, Weather, Travel and Sports).
Windows 8 also includes a Metro-style system component called PC Settings which exposes a small portion of Control Panel settings. Windows 8.1 improves this component to include more options that were previously exclusive to Control Panel.
Windows 8 introduces a new form of start menu called Start screen, which resembles the home screen of Windows Phone. This serves as the primary method of launching applications, and is shown in place of the desktop on startup. The Start screen consists of a grid of tiles which can be arranged into columnar groups. Tiles for apps can be either small (taking up 1 square) or large (taking up 2) in size. They can also display dynamic content provided by their corresponding apps, such as notifications and slide shows. The Start screen can uninstall apps directly.
Windows 8.1 improves the Start screen by the following changes:
Windows 8.1 reverts two changes that were featured in Windows 8. Windows 8 removed the Start button on the taskbar in favor of other ways of invoking the Start screen. Windows 8.1 restores this button. Windows 8 also showed the Start screen upon logon, as opposed to other editions of Windows that show desktop. In Windows 8.1, user may now choose which one to see first.
The Search charm opens a full screen display that can be used to search through various sources, including Apps, Settings, Files, and content surfaced by apps.
On Windows 8.1, the Search functionality was upgraded into a unified search system powered by Bing, which now uses a sidebar interface instead of taking over the entire screen. It can analyze a user's search habits to return relevant content stored locally and from the internet. Full-screen "hero" displays aggregate multimedia (such as photos, YouTube videos, songs/albums on Xbox Music) and other content (such as news articles and Wikipedia entries) related to a search query.
Windows 8 features a new lock screen, which includes a date and time display, along with the ability to display notifications from apps. Two new login methods optimized for touch screens are also available, including a four-digit PIN, or a "picture password"; which users allow the use of certain gestures performed on a selected picture to login. These gestures will take into account the shape, the start and end points, as well as the direction. However, the shapes and gestures are limited to tapping and tracing a line or circle. Microsoft found that limiting the gestures improved the speed of sign-ins by three times compared to allowing freeform methods. Wrong gestures will always deny a login, and it will lock out the PC after five unsuccessful attempts, until a text password is provided.
User accounts can be linked to a Microsoft account to provide additional functionality, such as the synchronization of user data, and integration with other Microsoft services such as Xbox Live, Xbox Music, Xbox Video (for gaming and multimedia) and SkyDrive online file storage.
Windows 8 includes improved support for multi-monitor configurations; the taskbar can now be shown on multiple displays, and each display can also show its own dedicated taskbar. Wallpapers can also be spanned across multiple displays, or each display can have its own separate wallpaper.
Windows 8.1 includes improved support for high-resolution monitors. A desktop scaling feature now helps resize the items on desktop to solve the visibility problems on tiny screens with very high native resolution.
Windows Explorer, which has been renamed File Explorer, now incorporates a ribbon toolbar, designed to bring forward the most commonly used commands for easy access. The "Up" button (which advances the user back a level in the folder hierarchy) that was removed from Explorer after Windows XP has also been restored. Additionally, File Explorer features a redesigned preview pane that takes advantage of widescreen layouts. File Explorer also provides a built-in function for mounting ISO, IMG, and VHD files as virtual drives.
Progress windows for file operations have also been redesigned; offering the ability to show multiple operations at once, a graph for tracking transfer speeds, and the ability to pause and resume a file transfer. A new interface has also been introduced for managing file name collisions in a file operation, allowing users to easily control which conflicting files are copied.
Libraries, introduced in Windows 7, can now have their individual icons changed through the user interface. Previously, users had to change icons manually by editing configuration files. Windows 8.1, however, no longer creates any default libraries for new users, and does not display the Libraries listing in File Explorer by default.
Windows 8 ships with Internet Explorer 10, which can run as either a desktop program (where it operates similarly to Internet Explorer 9), or as an app with a new full-screen interface optimized for use on touchscreens. Internet Explorer 10 also contains an integrated version of Flash Player, which will be available in full on the desktop, and in a limited form within the "Metro" app.
Windows 8.1 ships with Internet Explorer 11 which includes tab syncing, WebGL and SPDY support, along with expanded developer tools. The Metro version also adds access to favorites and split-screen snapping of multiple tabs.
Windows 8 provides clickable password peek icon on the right side of the password textbox.
File History is a continuous data protection component. File History automatically creates incremental backups of files stored in Libraries and user-specified folders to a different storage device (such as another internal or external hard drive, Storage Space, or network share). Specific revisions of files can then be tracked and restored using the "History" functions in File Explorer. File History replaces both Backup and Restore and Shadow Copy (known in Windows Explorer as "Previous Versions") as the main backup tool of Windows 8. Unlike Shadow Copy, which performs block-level tracking of files, File History utilizes the USN Journal to track changes, and simply copies revisions of files to the backup location. Unlike Backup and Restore, File History cannot back up files encrypted with EFS.
Windows 8 adds native support for USB 3.0, which allows for faster data transfers and improved power management with compatible devices. This native stack includes support for the newer, more efficient USB Attached SCSI (UAS) protocol, which is turned on by default even for USB 2.0 devices, although these must however have supporting firmware/hardware to take advantage of it. Windows 8.1 enhanced support for power saving features of USB storage devices, but this addition was not without problems, with some poorly implemented hardware degrading user experience by hangs and disconnects.
A port of Windows for the ARM architecture was also created for Windows 8. Known as Windows RT, it is specifically optimized for mobile devices such as tablets. Windows RT will only be able to run third-party Windows Store apps, but comes with a preinstalled version of Office 2013 specially redesigned for touchscreen use.
Alongside the existing WinPE-based Windows Setup (which is used for installations that are initiated by booting from DVD, USB, or network), Upgrade Assistant is offered to provide a simpler and faster process for upgrading to Windows 8 from previous versions of Windows. The program runs a compatibility check to scan the device's hardware and software for Windows 8 compatibility, and then allows the user to purchase, download, generate installation media with a DVD or USB flash drive and install Windows 8. The new installation process also allows users to transfer user data into a clean installation of Windows. A similar program, branded as Windows 8 Setup, is used for installations where the user already has a product key.
Windows 8 implements OEM Activation 3.0, which allows Microsoft to digitally distribute Windows licenses to original equipment manufacturers (OEMs). Windows 8 devices store product keys directly in firmware rather than printed on a Certificate of Authenticity (CoA) sticker. This new system is designed to prevent OEM product keys from being used on computers they are not licensed for, and also allows the installer to automatically detect and accept the product key in the event of re-installation.
Windows 8.1 Update adds a new installation mode known as "WIMBoot", where the WIM image that contains the Windows installation is left compressed rather than being extracted, and the system is configured to use files directly from within the system image. This installation method was primarily designed to reduce the footprint of the Windows installation on devices with small amounts of storage. The system image also doubles as the recovery image, speeding up Refresh and Reset operations. It is only supported in systems with UEFI firmware, where Windows is located on a solid-state drive or eMMC.
Windows 8 incorporates improved support for mobile broadband as a "first-class" method of internet connectivity. Upon the insertion of a SIM card, the operating system will automatically determine the user's carrier and configure relevant connection settings using an Access Point Name database. The operating system can also monitor mobile data usage, and changes its behavior accordingly to reduce bandwidth use on metered networks. Carriers can also offer their own dedicated Windows Store apps for account management, which can also be installed automatically as a part of the connection process. This functionality was demonstrated with an AT&T app, which could also display monthly data usage statistics on its live tile. Windows 8 also reduces the need for third-party drivers and software to implement mobile broadband by providing a generic driver, and by providing an integrated airplane mode option.
Windows 8 defaults to a "hybrid boot" mode; when the operating system is shut down, it hibernates the kernel, allowing for a faster boot on the subsequent startup. These improvements are further compounded by using all processor cores during startup by default. To create a more seamless transition between the Power-on self-test and Windows startup process, manufacturers' logos can now be shown on the Windows boot screen on compatible systems with UEFI firmware.
The Advanced Startup menu now uses a graphical interface with mouse and touch support in place of the text-based menu used by previous versions. As the increased boot speed of devices with UEFI can make it difficult to access it using keyboard shortcuts during boot, the menu can now be launched from within Windows—using either the PC Settings app, holding down Shift while clicking the Restart option in the Power menu, or by using the new "-o" switch on shutdown.exe. though the legacy version of the Advanced Startup menu can still be enabled instead.
Windows 8 also provides a platform that can be used to distribute and install UEFI firmware updates in a means identical to updating other device drivers on a system. A system's firmware can be exposed to Windows using a class driver, and updated firmware images can be distributed in a signed package with an INF file and security catalog. When the "driver" is installed, Windows prepares the update to be installed on the next boot, with the process itself queued by the Windows Boot Manager; the firmware update process occurs on a screen similar to the standard boot, but with a special status message displayed underneath the manufacturer's logo.
Windows 8 includes WDDM 1.2 and DirectX Graphics Infrastructure (DXGI) 1.2. The Desktop Window Manager now runs at all times (even on systems with unsupported graphics cards; where DWM now also supports software rendering), and now also includes support for stereoscopic 3D content.
Other major features include preemptive multitasking with finer granularity (DMA buffer, primitive, triangle, pixel, or instruction-level), reduced memory footprint, improved resource sharing, and faster timeout detection and recovery. 16-bit color surface formats (565, 5551, 4444) are mandatory in Windows 8, and Direct3D 11 Video supports YUV 4:4:4/4:2:2/4:2:0/4:1:1 video formats with 8, 10, and 16-bit precision, as well as 4 and 8-bit paletted formats.
Windows 8 adds support for printer driver architecture version 4. This adds a Metro friendly interface as well as changes the way the architecture was written.
Windows PowerShell is Microsoft's task automation framework, consisting of a command-line shell and associated scripting language built on .NET Framework. PowerShell provides full access to COM and WMI, enabling administrators to perform administrative tasks on both local and remote Windows systems. Windows 8 includes Windows PowerShell v3.0. Windows 8.1 comes with Windows PowerShell v4.0 which features a host of new commands for managing the Start screen, Windows Defender, Windows components, hardware and network.
Windows To Go is a feature exclusive to the Enterprise version of Windows 8 which allows an organization to provision bootable USB flash drives with a Windows installation on them, allowing users to access their managed environment on any compatible PC.
The Action Center introduced in Windows 7 is expanded to include controls and notifications in new categories, such as SmartScreen, drive status, File History, device software, and the new Automatic Maintenance feature, which can periodically performs a number of maintenance tasks, such as diagnostics, updates, and malware scans.
Windows 8 can now detect when a system is experiencing issues that have been preventing the system from functioning correctly, and automatically launch the Advanced Startup menu to access diagnostic and repair functions.
For system recovery, "Refresh" and "Reset" options (known internally as "Push-button reset") have been added, which allow a user to re-install Windows without needing to use installation media; both of these options reboot the system into the Windows Recovery Environment to perform the requested operation. Refresh preserves user profiles, settings, and Windows Store apps, while Reset performs a clean installation of Windows. The reset function may also perform specialized disk wiping and formatting procedures for added security. Both operations will remove all installed desktop applications from the system. Users can also create a custom disk image for use with Refresh and Reset.
On Windows RT, logging in with a Microsoft account automatically activates passive device encryption, a feature-limited version of BitLocker which seamlessly encrypts the contents of mobile devices to protect their contents. On Windows 8.1, device encryption is similarly available for x86-based Windows devices, automatically encrypting user data as soon as the operating system is configured. When a user signs in with a Microsoft account or on a supported Active Directory network, a recovery key is generated and saved directly to the user's account. Unlike BitLocker, device encryption on x86-based devices requires that the device meet the Connected Standby specifications (which among other requirements, requires that the device use solid state storage and have RAM soldered directly to the motherboard) and have a Trusted Platform Module (TPM) 2.0 chip.
Windows 8 includes an updated Windows Defender, an antivirus program that defends the system against a broad range of malware including computer viruses, computer worms and spyware. Windows 8.1 augments it with network inspection system (NIS), a network intrusion detection system. This feature has been present in Microsoft Security Essentials since July 2010.
Windows 8 integrates Windows Live Family Safety into the operating system, allowing parents to restrict user activity via web filtering, application restriction, and computer usage time limits. Parental controls functionality, introduced in Windows Vista, was previously partially removed in Windows 7 and made a part of Windows Live Family Safety instead.
Windows 8 supports the secure boot mechanism on supported UEFI systems. It uses a public-key infrastructure process to verify the integrity of the Windows boot loader—preventing malware from infecting the system before the operating system loads. Windows 8.1 displays an on-screen watermark on the desktop if the system supports secure boot but it is disabled, however a patch was later released to remove the watermark.
Storage Spaces is a storage virtualization technology which succeeds Logical Disk Manager and allows the organization of physical disks into logical volumes similar to Logical Volume Manager (Linux), RAID1 or RAID5, but at a higher abstraction level.
A storage space behaves like a physical disk to the user, with thin provisioning of available disk space. The spaces are organized within a storage pool, i.e. a collection of physical disks, that can span multiple disks of different sizes, performance or technology (USB, SATA, SAS). The process of adding new disks or replacing failed or older disks is fully automatic, but can be controlled with PowerShell commands. The same storage pool can host multiple storage spaces. Storage Spaces have built-in resiliency from disk failures, which is achieved by either disk mirroring or striping with parity across the physical disks. Each storage pool on the ReFS filesystem is limited to 4 PB (4096 TB), but there are no limits on the total number of storage pools or the number of storage spaces within a pool.
A review in Ars Technica concluded that "Storage Spaces in Windows 8 is a good foundation, but its current iteration is simply too flawed to recommend in most circumstances." Microsoft MVP Helge Klein also criticized Storage Spaces as unsuitable for its touted market of SOHO users.
Storage Spaces was further enhanced in Windows Server 2012 R2 with tiering and caching support, which can be used for caching to SSD; these new features were not added to Windows 8.1. Instead Windows 8.1 gained support for specific features of SSHD drives, e.g. for host-hinted LBA caching (TP_042v14_SATA31_Hybrid Information).