welding is a way of heating pieces of metal using electricity or a flame so that they melt and stick together. there are many kinds of welding, including arc welding, resistance welding, and gas welding. the most common type is arc welding. anyone who is near arc welding needs to wear a special helmet or goggles because the arc is so bright. looking at the arc without visual protection may cause permanent eye damage. it is also important to cover all your skin because it can give you something like a sunburn. hot sparks from the weld can burn any skin that is showing. one kind of welding that does not use an arc is oxy-fuel welding (ofw), sometimes called gas welding. ofw uses a flame to heat up the metal. there are other kinds of welding that do not use an arc.