"Windows Driver Foundation (WDF) contains a framework for the creation of user-mode drivers. The User-Mode Driver Framework (UMDF) provides a unified model that can work across device classes. This framework integrates the installation and management of the devices with standard operating system facilities, such as Plug and Play (PnP) and power management.
UMDF supports protocol device classes such as cameras and portable music players. Moving drivers for such devices into user mode can simplify the drivers and improve the overall stability of the operating system.
UMDF is based on the same conceptual driver programming model as the Kernel-Mode Driver Framework (KMDF), which is also part of WDF. However, the two frameworks implement the model with different components, device driver interfaces (DDIs), and data structures.
The UMDF library is included in the Windows Vista and later versions of the Windows Driver Kit (WDK).
You can develop and build UMDF drivers for Windows XP or later versions of Windows." (Microsoft)