Welding is a process that involves joining two or more metal parts by melting and fusing them. TIG/GTAW, MIG/SMAW, and CO2 are some of the most common types of welding techniques used in various industries. TIG/GTAW (Tungsten Inert Gas/Gas Tungsten Arc Welding) is a welding process that uses a tungsten electrode to produce the weld. MIG/SMAW (Metal Inert Gas/Shielded Metal Arc Welding) uses a wire electrode and a shielding gas to protect the weld from contamination. CO2 (Carbon Dioxide) welding uses a wire electrode and a stream of carbon dioxide gas to protect the weld.