Metal Inert Gas (MIG) welding uses an electric arc that form between a consumable MIG wire electrode and the metal work piece, causing the metal to heat and join. The inert gas acts as a shield the welding processes from atmospheric contamination. Often applied to steel because it allows for faster welding times compared to other welding processes. MIG welding is a good process for first time welders to start learning how to join two pieces of metal.