Forums → The Tavern → What program is this?

I was on Youtube, and this taskbar-esque thing popped up on the bottom of the screen. I don't know if I clicked on something, or if it just came up. It has not come up since the first time the taskbar popped up. No one that uses this computer remembers installing it. It had a bunch of options, but the one I clicked on was 3D view, that's what the screenshots are. Anyone know what this is?
The screenshots are of the 3D View, you can see the taskbar at the bottom.