WDM may refer to any of the following:
1. Short for Windows Driver Model, WDM is a strategy for making Microsoft Windows drivers easier to develop. WDM unified the driver models for Windows 98 and 2000 by setting standards, thus reducing the amount of code needed to write each program. It should be noted that WDM is not backward compatible with older versions of Windows.
2. Short for Wavelength Division Multiplexing, WDM is a method of modulating each laser light being simultaneously sent down the same optical fiber.