The joining technology is used in any type of mechanical joint which is the arrangement formed by two or more elements: typically, two physical parts and a joining element. The mechanical joining systems make possible to form a set of several pieces using the individual parts and the corresponding joining elements. There are fixed sets and removable sets.

Most common utensils (tools, furniture, weapons, clothing, footwear, vehicles, et cetera) are made up of sets of parts. The study of