User blog comment:G0LD3NF1RE/Dawnguard encounters issues with Playstation/@comment-173.180.201.88-20120902025305/@comment-3202167-20120902031502

I am too lazy to explain myself, so copy+paste: 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 Direct X was coined as shorthand term for all of these APIs (the X standing in for the particular API names) 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. [1] 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.

Direct3D (the 3D graphics API within DirectX) is widely used in the development ofvideo games for Microsoft Windows, Microsoft Xbox, Microsoft Xbox 360 and someSega Dreamcast games. Direct3D is also used by other software applications for visualization and graphics tasks such as CAD/CAM engineering. As Direct3D is the most widely publicized component of DirectX, it is common to see the names "DirectX" and "Direct3D" used interchangeably.

X360 and PC do share few similiar aspects, but that is really it.