Direct2D

Direct2D is an application programming interface (API) designed for the rendering of 2D graphics (Direct3D is used for 3D graphics rendering) for applications that required high performance graphics rendering. It is part of the Microsoft DirectX package of APIs for video and audio development. Originally designed for the Windows 7 and Windows Server 2008 operating systems, Direct2D has been ported to Microsoft's Windows Vista operating system too.

Other DirectX related glossary:

DirectDraw
Direct2D
Direct3D
DXGI
DirectInput
DirectPlay
DirectPlay Voice
DirectSound
DirectSound3D
DirectMusic
DirectX Audio
DirectX Media
DxDiag
DirectX Media Objects
DirectSetup
XAudio2