Windows Vista is a row of operating systems developed by Microsoft for apply on PCs, with home and business desktops, laptops, tablet PCs, and media center PCs. Windows Vista was known by its codename "Longhorn." After development was finished it was out for PC hardware and software makers, business customers, and retail channels. Then it was released worldwide and available for buy and download from Microsoft's website. Windows Vista released take more than five years after introduction of its predecessor, Windows XP, the highest time period between consecutive releases of Microsoft Windows desktop OS. It was succeeded by Windows 7.

Windows Vista have several modifications and latest features, with an efficient GUI and visual style named Windows Aero, a redesigned search function, multimedia tools with Windows DVD Maker, and redesigned networking, audio, print, and show sub-systems. Vista wants to increase level of communication between machines on home network, using peer-to-peer technology to simplify sharing files and digital media between PCs and devices. Vista contains version 3.0 of .NET Framework, allocating software developers to write applications without usual Windows APIs.

Microsoft's main declared object with Windows Vista to develop state of security in operating system. One general analysis of Windows XP and its predecessors is their generally broken security vulnerabilities and generally vulnerability to malware, viruses and buffer overflows. By this, company-wide "Trustworthy Computing initiative" which wants to include security work into each feature of software development at company. Microsoft declared that it prioritized improving security of XP and Server 2003 above finishing Windows Vista, thus delaying its completion.

While these new features and security developments got positive reviews, Vista has also been target of a lot criticism and negative press. Criticism of Vista has targeted its high system requirements, its limiting licensing conditions, the addition of many latest digital rights management technologies wanted at limiting copying of secured digital media, need of compatibility with various pre-Vista hardware and software, and many authorization prompts for User Account Control.

Thus result of these and other topics, Windows Vista had seen primary approval and satisfaction rates lower than Windows XP. Though, with an anticipated 330 million internet users, it declared that Vista usage had exceeded Microsoft’s pre-launch two year out expectations of getting 200 million users. Windows Vista is second most broadly used operating system on internet with an approximately 23% market share, the most broadly used being Windows XP with an approximately 69% market share.