a "Virtual Device Driver", so named for the "
A special type of Windows driver. VxDs run at the most privileged CPU mode (ring 0) and allow low-level interaction with the hardware and internal Windows functions.
Virtual Device Driver A device driver under Windows 3.x/Windows 95 running as part of the kernel and thus having access to the memory of the kernel and all running processes as well as raw access to the hardware. VxD's usually have the filename extension .386 under Windows 3.x and .vxd under Windows 95. VxD's written for Windows 3.x can be used under Windows 95 but not vice versa.
virtual device driver. A special type of device driver that has access to the core of the operating system for supervising hardware operations directly. A mouse, serial port and parallel port use VxDs.
Virtual Device Driver. A low level (CPU-privileged) interaction between a hardware device and an operating system.
A Windows program which can run in the background. A scanner implemented as a VxD has all the advantages of a DOS TSR, but can have additional advantages: for instance, a good VxD will scan continuously.
Virtual Device (file name extension) [Microsoft