DirectX is a Software Development Kit (SDK) is a set of low-level API's made for creating High-Performance Multi-Media Applications and Games.

Components to DirectX are as follows:

**Direct3D **- This is what we'll be learning first. Direct3D is used to make our 3D worlds and all that using hardware acceleration. This is where all the graphics and text and everything you see on the screen come from. Direct3D simplifies advanced graphics programming. 

**DirectSound **- DirectSound provides High-Performance sounds and audio for your Multi-Media application or game. It can play or capture waveform audio. 

**DirectInput **- Windows does a fine job with keyboard and mouse input, but DirectInput has full Force-Feedback Compatibility. Like a joystick that rumbles or something. 

**DirectDraw **- Was used for 2D graphics programming, but isn't recomended anymore because Direct3D does both 2D and 3D graphics programming.
As time goes on, DirectX gets bigger and better. There are a LOT of things DirectX can do now, So Visit www.msdn.com and check out the DirectX documentary if you wanna learn more about it.