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.
WDDM provides the functionality required to render the desktop and applications using Desktop Window Manager, a compositing window manager running on top of Direct3D. It also supports new DXGI interfaces required for basic device management and creation.
The WDDM specification requires at least Direct3D 9-capable video card and the display driver must implement the device driver interfaces for the Direct3D 9Ex runtime in order to run legacy Direct3D applications; it may optionally implement runtime interfaces for Direct3D 10 and higher.