Windows Vista :

Windows Vista (codenamed Longhorn) is an operating system by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs and media center PCs. Development was completed on 8 November 2006,and over the following three months, it was released in stages to computer hardware and software manufacturers, business customers and retail channels. On 30 January 2007, it was released worldwide and was made available for purchase and download from the Windows Marketplace. The release of Windows Vista came more than five years after the introduction of its predecessor, Windows XP, the longest time span between successive releases of Microsoft Windows desktop operating systems. It was succeeded by Windows 7, which was released to manufacturing on 22 July 2009 and released worldwide for retail on 22 October 2009.

While these new features and security improvements have garnered positive reviews, Vista has also been the target of much criticism and negative press. Criticism of Windows Vista has targeted its high system requirements, its more restrictive licensing terms, the inclusion of a number of, then, new DRM technologies aimed at restricting the copying of protected digital media, lack of compatibility with some pre-Vista hardware and software, longer boot time, and the number of authorization prompts forUser Account Control. As a result of these and other issues, Windows Vista had seen initial adoption and satisfaction rates lower than Windows XP. However, with an estimated 330 million Internet users as of January 2009, it had been announced that Vista usage had surpassed Microsoft's pre-launch two-year-out expectations of achieving 200 million users. At the release of Windows 7 (October 2009), Windows Vista (with approximately 400 million Internet users) was the second most widely used operating system on the Internet with an approximately 19% market share, the most widely used being Windows XP with an approximately 63% market share. In May 2010, Windows Vista's market share had an estimated range from 15% to 26%. On 22 October 2010, Microsoft ceased sales of retail copies of Windows Vista, and the OEM sales for Vista ceased a year later. As of September 2017, Vista's market share was 0.43%.

Microsoft stopped providing extended support for Windows Vista on 11 April 2017.