What is the NVIDIA HD Audio Driver for?

Does the company make sound cards or something? Do I need that installed? My sound is onboard Realtek HD. Also there’s something called NVIDIA Virtual Audio installed.

Finally, since I don’t have a 3D monitor, I’m pretty sure I don’t need the 3D driver and the 3D Controller driver, which Nvidia’s driver installers install by default.

HDMI/DVI audio

Yeah, HDMI audio. I disable all that crap on install too.