A Video Grabber Windows driver refers to the software that allows your computer to interface with a video capture device (often referred to as a video grabber or video capture card). These devices allow you to capture video from external sources such as VHS tapes, analog cameras, DVD players, or even streaming video feeds. The driver enables the video grabber to function correctly with your Windows operating system, allowing software (such as video editing software, streaming applications, or media players) to access and capture video from the device.