DirectX 11

Microsoft DirectX is a collection of application programming interfaces (APIs) for handling tasks related to multimedia, especially game programming and video, on Microsoft platforms. Originally, the names of these APIs all began with Direct, such as Direct3D, DirectDraw, DirectMusic, DirectPlay, DirectSound, and so forth. The name DirectX was coined as shorthand term for all of these APIs and soon became the name of the collection. When Microsoft later set out to develop a gaming console, the X was used as the basis of the name Xbox to indicate that the console was based on DirectX technology.The X initial has been carried forward in the naming of APIs designed for the Xbox such as XInput and the Cross-platform Audio Creation Tool (XACT), while the DirectX pattern has been continued for Windows APIs such as Direct2D and DirectWrite.

DirectX 11
Microsoft unveiled DirectX 11 at the Gamefest 08 event in Seattle, with the major scheduled features including GPU support (DirectCompute), and Direct3D 11 with tessellation support and improved multi-threading support to assist video game developers in developing games that better utilize multi-core processors. Direct3D 11 runs on Windows Vista, Windows 7, Windows 8 and Windows 10. Parts of the new API such as multi-threaded resource handling can be supported on Direct3D 9/10/10.1-class hardware. Hardware tessellation and Shader Model 5.0 require Direct3D 11 supporting hardware. Microsoft has since released the Direct3D 11 Technical Preview.Direct3D 11 is a strict superset of Direct3D 10.1 — all hardware and API features of version 10.1 are retained, and new features are added only when necessary for exposing new functionality. This helps to keep backwards compatibility with previous versions of DirectX.