Windows 7 (previously known as "Vienna" and before that, "Blackcomb") is the name for the version of Microsoft's Windows operating system preceding Windows 8, originally announced in February 2000, but was subject to major delays such as Windows XP SP2 and Windows Vista (which was also delayed by XP SP2). "Seven" was released on October 22, 2009. Work on Windows 7 began right after Windows Vista was released. Some early details of a few core operating system features surfaced at developer conferences such as WHEC in 2006.
History & Development
The codename "Windows Blackcomb" was first assigned to Windows NT 6.0, an operating system that was planned to follow Windows XP. Blackcomb was supposed to be the successor to both Windows XP (Windows NT 5.1) and Windows Server 2003 (Windows NT 5.2). In late 2001 "Blackcomb" was said to be scheduled for release in 2005 then in August it was announced that a minor intermediate release, codenamed Windows "Longhorn", would release in 2002 to update the Windows NT 5.x line. In the years that followed "Longhorn" was transformed to include many features previously promised for "Blackcomb" and became Windows NT 6, and was given a name, Windows Vista. The codename "Blackcomb" was eventually discarded, however the ideas and features behind "Blackcomb" that were not included in Windows Vista got a new name codename Windows "Vienna". Windows Vista's successor (Windows 7) was released in late 2009.
Sources in Microsoft have stated that Windows 7 will not just be a major change to Windows, but a complete departure from the way users today usually think about using a computer. For example, the "Start" and "Taskbar" philosophy, introduced in Windows 95, might be replaced by a "new interface" that was said in 1999 to be scheduled for Windows 7 ("Vienna"). While Windows Vista was intended to be an evolutionary release, Windows Vienna is targeted directly at revolutionizing the way users of the product interact with their PCs.
"That means that right now when you move from one PC to another, you've got to install apps on each one, do upgrades on each one. Moving information between them is very painful. We can use Live Services to know what you're interested in. So even if you drop by a [public] kiosk or somebody else's PC, we can bring down your home page, your files, your fonts, your favorites and those things. So that's kind of the user-centric thing that Live Services can enable. [Also,] in Vista, things got a lot better with [digital] ink and speech, but by the next release there will be a much bigger bet. Students won't need textbooks; they can just use these tablet devices. Parallel computing is pretty important for the next release. We'll make it so that a lot of the high-level graphics will be just built into the operating system. So we've got a pretty good outline."
Microsoft released Windows 7 at the end of 2009.
Microsoft originally had planned for Vista to include a number of big changes to Windows, including a new file system (WinFS) and a completely new user interface, but after Windows XP was hit by huge worm outbreaks in 2003, Microsoft moved almost all of its entire engineering team to locking down Windows with the XP SP2 release.
"We put Longhorn on the back burner for awhile," Fathi said. "Then when we came back to it, we realized that there were incremental things that we wanted to do, and significant improvements that we wanted to make in Vista that we couldn't deliver in one release."
Windows 7 includes many new features, such as support for touch screen interfaces which lets users draw on the computer screen like a piece of paper. Unlike in previous operating systems, Microsoft decided on many of these new features in conjunction with major computer manufacturers. Microsoft also redesigned the user interface in many applications, including Paint and Wordpad, which now sport the ribbon interface that Microsoft first introduced in several Office 2007 applications.
Software developers are given a shortcut to various internal settings. Dubbed "GodMode" by bloggers; it was not something Microsoft used internally to refer to the undocumented settings folders. Apparently, it has been included since Windows Vista but never discussed by Microsoft until bloggers stumbled upon it. 
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