pin, the small, pointed and headed piece of stiff wire used to secure clothing or papers. In mechanical and civil engineering the term pin, or more properly pin fastener, designates a peg- or boltlike device designed to fasten machine and structural components together or to keep them properly aligned.

Bronze pins 2 to 8 inches (5 to 20 cm) long with gold heads or decorative gold bands have been found in ancient Egyptian tombs. The Greeks and Romans used pins or brooches similar to the safety pin for fastening their clothing. In medieval Europe, skewers of wood, bone, ivory, silver, gold, or brass were used, elaborately fashioned for persons of wealth and simply made of wood for common people. By the end of the 15th century the manufacture of pins from drawn iron wire was well established, particularly in France.

Pinmaking machines were introduced early in the 19th century. In New York John Ireland Howe founded a successful factory with his improved machines, while in 1838 in Birmingham, Eng., Daniel Foot-Tayler profitably applied the pinmaking patent (1824) of Lemuel W. Wright. Subsequently many pinmaking machines were developed, including devices for thrusting finished pins through crimped papers. Modern machines are completely automatic.