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 center PCs. 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, and was made available for purchase and download from Microsoft's website. 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.
Windows Vista contains many changes and new features, including an updated graphical user interface and visual style dubbed Windows Aero, improved searching features, new multimedia creation tools such as Windows DVD Maker, and redesigned networking, audio, print, and display sub-systems. Vista also aims to increase the level of communication between machines on a home network, using peer-to-peer technology to simplify sharing files and digital media between computers and devices. Windows Vista includes version 3.0 of the .NET Framework, which aims to make it significantly easier for software developers to write applications than with the traditional Windows API.
For graphics, Vista introduces a new Windows Display Driver Model and a major revision to Direct3D. The new driver model facilitates the new Desktop Window Manager, which provides the tearing-free desktop and special effects that are the cornerstones of Windows Aero. Direct3D 10, developed in conjunction with major display driver manufacturers, is a new architecture with more advanced shader support, and allows the graphics processing unit to render more complex scenes without assistance from the CPU. It features improved load balancing between CPU and GPU and also optimizes data transfer between them.
At the core of the operating system, many improvements have been made to the memory manager, process scheduler and I/O scheduler. The Heap Manager implements additional features such as integrity checking in order to improve robustness and defend against buffer overflow security exploits, although this comes at the price of breaking backward compatibility with some legacy applications. A Kernel Transaction Manager has been implemented that enables applications to work with the file system and Registry using atomic transaction operations.