According to the YouTube poster, this is a clip from the show The Secret Life of Machines. In the video, the host describes the concepts behind the electric light — specifically the idea of resistance heating to create light. Here comes the fun part, though: he demonstrates with a welding power supply and some good old wire and carbon filament.
As you might imagine, it gets a little messy. I love the first YouTube comment: “Molten metal? I’ll just brush it aside with my tweed jacket cuff.” Heh.
Anyway, don’t try this at home (obviously), and have a good weekend (doing safer things in the shop).