DirectX

Microsoft DirectX is a collection of highly functional application programming interfaces (APIs) designed to handle various multimedia-related tasks, such as video playback and game development on Microsoft platforms. The collection includes Direct3D, DirectDraw, DirectMusic, DirectPlay, DirectSound, and more. The umbrella term for all of these is DirectX.

In recent years, Microsoft has expanded DirectX to include additional multiplatform game development APIs like XInput, which are meant to enhance or replace individual components of DirectX. Among these APIs, Direct3D stands out as the most publicized and widely used in the development of video games for Microsoft Windows, Microsoft Xbox, and Microsoft Xbox 360. Besides game development, Direct3D is also essential in software applications requiring 3D visualization and graphics tasks, such as computer-aided design and manufacturing engineering.

Generally, the DirectX software development kit (SDK) contains runtime libraries for easy integration into development projects, together with accompanying headers and documentation for hassle-free coding. In the past, the runtimes only became available via game installation or by user consent. DirectX was absent in Windows 95, but it was included in Windows 95 OEM Service Release 2. Every subsequent Windows version has integrated DirectX in their system, and the SDK is also available as a free download. Although the runtimes remain proprietary, the source code of most SDK samples is open-source.

Currently, Direct3D has two significant releases, Direct3D 10 and Direct3D 9Ex, which only work for Windows Vista. This is due to their dependence on the new Windows Display Driver Model (WDDM) introduced specifically for Windows Vista. The WDDM graphics architecture features a video memory manager that permits multiple applications to virtualize graphics hardware and services like the Desktop Window Manager.