TIG welding differs from the MIG and MAG techniques. Despite the fact that it is also an arc welding operation, this process of joining materials does not use a consumable electrode, but heats up and melts the material being welded. As a complement to the process, a special wire, rod or stick is used, which also undergoes melting close to the glowing arc. As molten metals are extremely vulnerable to oxidation during this process, an inert gas is used as a shield (similar as in the MIG method).