DirectX is the name of a collection of game programming interfaces for the Microsoft Windows platform. DirectX includes API’s for sound, graphics, input, networking and other game related functions.

DirectX is often required by computer games that run on Windows. DirectX 9x is available for download for Windows XP. DirectX 10 is the latest version available only with Windows Vista.

DirectX has been used to develop games for Windows, the Xbox, the Xbox 360 and the Sega Dreamcast.

DirectX 10 represents the current state of the art for Windows development. Its the foundation that the user interface for Windows Vista is built upon. DirectX 10 should also enable much better graphics for games that support it.

According to Microsoft DirectX 10 should be able to render graphics up to 8 times faster than DirectX 9. DirectX 10 supports Shader Model 4.0.