Microsoft Directx 9.0c JUNE 2010 Offline Installer is a collection of API (Application Program Interface) which functions to handle tasks related to Multimedia, such as Graphics, SOUND, 3D animation, Video. Actually, in the past, DirectX was called an application interface, all of which started from DirectX, such as DirectMusic, Direct Play, Direct3D, and so on, but now we know DirectX which has been collected into one.