MIG, or metal arc, welding uses a spool of wire to join long stretches of metal. Like TIG welding, MIG welding also uses inert gas to protect the weld from the environment.
Soldering & Brazing
Soldering and brazing involves the use of molten metal to fuse pieces of metal, but at a far lower temperature than welding. These techniques are often used for small parts, as well as electric and electronic parts.
Standard arc welding uses metal rods and gas flux to produce electrical currents that create enough heat to melt metal.
TIG, or tungsten arc, welding, uses stainless steel or aluminum rods to produce melting heat, and blows inert gas to protect the weld from environmental factors.