Metal forming is a type of metal fabrication process that involves reshaping metals without melting them. Avoiding the added challenges of handling molten materials, this process relies on the plasticity of certain metals. A common type of metal forming is stamping, whereby a press creates creases or indentations in sheet metal. Operators feed the sheet metal in the slot between the top and bottom of the press, which can operate on mechanical, pneumatic, or hydraulic power. Stamping is effective for custom prototyping as well as high-volume production runs.