A staple is a U-shaped metal form, usually made of wire with chisel-pointed ends, that can be driven into a surface with a hammer or with a more specialized device: either a stapler or a see thumbnail to leftstaplegun. "Staple" is also a verb meaning to drive a staple. Staples are most commonly used on paper, corrugated cardboard, and wood. Contemporary painters typically attach canvas to stretcher by stapling it with a staplegun; either electric powered or spring driven. Staples, staplers, and stapleguns are commercially available in many types and sizes, produced by many manufacturers. Before their invention, what painters do with staples was often accomplished with tacks and adhesives.Also see frame, join, and nail.