Windows Vista

Windows Vista (codenamed Longhorn) is an operating system by Microsoft, released to manufacturing on November 8, 2006 and general availability on January 30, 2007. It is the seventh operating system in the Windows NT operating system line, succeeding Windows XP and preceding Windows 7. It also had one of the longest development periods in Microsoft's history starting in May 2001 and continuing until November 2006.

Development
The "Longhorn" project started in earnest in May 2001, originally intended as a bridging release between Whistler and the later version of Windows codenamed Blackcomb. As development progressed, many features slated for Blackcomb became part of Longhorn, and employees jumped ship from other parts of the company. As development progressed before the reset, Longhorn became a heavily bloated and unstable piece of vaporware, with release dates being pushed back on several occasions. The first build to leak publicly was build 3683, which contained a new theme and also the foundations for Windows Future Storage (aka WinFS) and Avalon (the codename for the Windows Presentation Foundation (WPF) framework).

Stability increasingly became an issue as development progressed, and very few builds were publicly released as a result. Only two builds were distributed at conferences and to developers: build 4051 and build 4074. The last known confirmed build from before the development reset is build 4093. At 16:29 on August 19, 2004, (the same day as the compilation of 4093), Microsoft reset the development of Windows Longhorn and started fresh using Windows Server 2003 Service Pack 1 as a codebase, starting the Omega-13 period. Immediate post-reset builds were primarily focused on reintegrating features from the pre-reset builds while maintaining stability. Most of these builds are similar to Windows XP in the overall look and feel. Few builds from this stage of development have been released, officially or otherwise. Development of Longhorn continued, albeit many features originally slated for inclusion were delayed or dropped to produce a more realistic set of goals for the OS. Examples of said features include WinFS, "Castle" (later shipped in Windows 7 as HomeGroup) and what would become Windows PowerShell.

In April 2005, a pre-beta build was released to testers (build 5048). This build showed the progress made since the reset and also proved much more stable than previous builds. Build 5112 (Beta 1) was released to the public soon afterward in July and showcased an early version of the Aero interface, as well as many stability improvements over XP. Later that year and the next year, many builds were released to testers in a public beta program, with builds dubbed as "Community Technology Previews" (CTPs). The final build that was pushed out to public preview testers was Release Candidate 2 (build 5744). The RTM build was build 6000.16386, compiled on November 8, 2006.

Editions
Windows Vista came in many editions. Unlike Windows XP, there was no special edition for Media Center and 64-bit capability, since these features were included in at least one of the consumer editions. Windows Vista also did not have an embedded version, perhaps due to the considerable grunt required to run optimally.


 * Starter: This edition is intended for emerging markets and low-cost PCs. As in XP, the three-program limit was there, and only 1GB RAM was accepted. Other software restrictions applied as well. This version is hence not available in 64-bit.
 * Home Basic: Found in low cost to mid-end, this version of Windows Vista does not fully have Aero (though it has DWM) and hence does not have effects like transparency and 3D Flip. Windows Media Center is also not present in this edition. Parental Controls are included, however. Unlike the Starter edition, it does not have the hardware and 3-program limit.
 * Home Premium: The consumer version of Windows Vista, this version includes full Aero functionality and Windows Media Center. It also includes Premium Games (eg - InkBall).
 *  Business: The business-oriented version of Windows Vista, it contains several features like full RDP (client/host) capability, Group Policy, and domain joinability. However, Windows Media Center and Parental Controls are not included, and Premium Games are disabled by default.
 * Ultimate: The top consumer variant of Windows Vista, it is a merger of the features included Windows Vista Home Premium and Business. BitLocker is included in this version.
 * Enterprise: The business variant of Windows Vista. It is similar to Ultimate, but without Windows Media Center and includes enterprise-specific tools.

Myths and legends
No build of Windows Vista (including pre-reset) used or even included the widespread sound scheme that appears in several fanmade Longhorn or Vista themes, which was actually a sound scheme titled "Deep Fantasy", commercially available on NEO Sounds, a stock sound/music website in the 2000s. The Windows XP sounds remain and are used in all pre-reset builds, with a few being swapped with Vista sounds between builds builds 5469 and 5840.16384.

The alleged Windows Vista Beta 1 startup is actually  used in the Speech Recognition tutorial in build 5308.6 and onwards. Likewise, the alleged Windows Vista Beta 2 startup is actually a jingle used in Vista Beta 2 Help video outros.

Alpha
 Milestone 3 

Development reset
These builds are also referred to as Omega-13 builds.