Windows Display Driver Model
Windows Display Driver Model (WDDM) is the graphic driver architecture for video card drivers running Microsoft Windows versions beginning with Windows Vista.
It is a replacement for the previous Windows 2000 and Windows XP display driver model XDDM/XPDM and is aimed at enabling better performance graphics and new graphics functionality and stability. Display drivers in Windows Vista and Windows 7 can choose to either adhere to WDDM or to XDDM. With the removal of XDDM from Windows 8, however, WDDM became the only option.