Most video footage you see of welding just looks like a blinding light and some sparks. mrbean022387 added an appropriate soundtrack to Vurt Runner’s super-macro footage of gas metal arc welding as a tiny pool of molten metal burbles and coalesces.
While much welding is done by adding molten hot metals with a torch or electrical current, friction welding creates strong joints by rubbing metal together at a high speed. Here, two blocks of titanium are merged into one. If you thought that was cool, check this out.