A welder machine is a device that generates heat to melt and join metal pieces together. There are several types of welder machines, including stick welders, which use an electric current to create an arc between a metal stick and the metal being welded, and MIG (metal inert gas) welders, which use a wire electrode and an inert gas to create an arc. Welder machines may be portable, allowing the welder to take them to various job sites, or stationary, with the welding work taking place in a workshop or factory. Welder machines typically have several adjustable settings, such as the amperage and voltage of the current, to allow the welder to fine-tune the welding process for different materials and thicknesses of metal.