Last week I've got a hands on experience in welding, which I must say is not like what I expected. It's not that easy, requires years of training to get the best welding job and the equipment is not expensive stuff. I always thought that I could weld very well, although a bit ironic I must say since my soldering skills really sucks.
The workshop guy explaining to us about the science of welding:
Ha ha master welder Ariff is in town.
The mask uses some sort of polarizing filter, which cuts off probably 80% of the light.
A video of the welding process.
There are also other welding types other than electrical, like this one, oxyacetylene welding.
I cannot remember what this type of welding is called, but can be use for quick adhesion.