Windows Vista (pronounced /ˈvɪstə/) is a line of operating systems developed by Microsoft for use on personal computers, including home and business desktops, laptops, Tablet PCs, and media centers. Prior to its announcement on July 22, 2005, Windows Vista was known by its codename "Longhorn". Development was completed on November 8, 2006; over the following three months it was released in stages to computer hardware and software manufacturers, business customers, and retail channels. On January 30, 2007, it was released worldwide to the general public, and was made available for purchase and downloading from Microsoft's web site. The release of Windows Vista comes more than five years after the introduction of its predecessor, Windows XP, to date the longest elapsed time between successive releases of Microsoft Windows.
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