The new guidelines presented in PC 97 Hardware Design Guide define PC system types and component requirements for the Microsoft Windows family of operating systems. This means that, for the first time, the "Designed for Microsoft Windows" program requirements are defined in one place for two operating systems:
In 1996, Windows 95 and Windows NT 4.0 share such technologies as the Win32 API, OLE, networking, and user interface, so it is possible to run applications based on a common API set and a common object technology. Both products contain the essential infrastructure for desktop management by using a system registry that is accessible remotely using Win32 APIs.
In the future, these operating systems will share even more capabilities, including the Win32 Driver Model (WDM), the new Advanced Configuration and Power Interface (ACPI), and Plug and Play capabilities, as described in the "OnNow and WDM for PC 97" chapter. Other shared capabilities will include Microsoft DirectX™ APIs, ActiveX™ APIs, and distributed Component Object Model protocol (formerly referred to as "network OLE"). Because of differences in product development cycles, new technologies might appear on one product before the other, but these differences will be temporary.
All support for new technologies such as USB input devices and IEEE 1394 digital video devices will use WDM. To take advantage of new support in both operating systems, the hardware manufacturer can use the built-in drivers or create only a minidriver to exploit specific features in the hardware.
Although more code will be shared on both platforms over time, there will continue to be two complementary desktop operating system products to meet the diverse needs of business and end users.