The TerraTV WDM Crossbar Windows driver is a specific device driver used for video capture cards or TV tuners manufactured by TerraTec, a company known for making multimedia hardware, including TV tuners, sound cards, and video capture devices. Like the BT878 WDM Crossbar driver (which is used for Brooktree/BTech-based capture cards), the TerraTV WDM Crossbar driver is a Windows driver that enables video capture functionality and provides the crossbar functionality, which allows routing of video input signals (such as from a TV antenna, cable, or video input) to the computer.

The driver is required for TerraTec's TV tuner cards or capture devices (like TerraTV) to properly interface with the Windows operating system, so that users can capture video, watch TV, or use the device for other multimedia purposes. The WDM in the name refers to the Windows Driver Model, which is a framework for writing device drivers that are compatible with different versions of Windows.