Win32 Driver Model

The Win32® Driver Model (WDM) is designed to allow binary compatibility for targeted device classes written for Windows 98 and Windows NT 5.0 and future versions of these operating systems. For bus and device classes with WDM support, driver developers write only small minidrivers to expose device-specific features and can maintain one driver source-code library for minidrivers that run on both Windows 98 and Windows NT.

The WDM core provided by Microsoft for Windows 98 and Windows NT 5.0 is a subset of Windows NT kernel services, with new cross-platform application programming interfaces (APIs) for Plug and Play and power management. For each bus class and device class with WDM-based support, Microsoft provides a class driver, which is a device abstraction for a particular class of devices.

Microsoft provides the WDM core services, which are documented in the Windows NT 5.0 DDK. WDM support for Windows 98 and Windows NT includes the following:

Key support for many devices relies on the WDM Stream class driver, which optimizes data flow in the operating system kernel.

For related PC 98 requirements, see the driver requirements for the specific bus and device class that includes WDM support in Windows 98 and Windows NT 5.0. Implementation details are provided in the Windows NT 5.0 DDK.