A snap fastener, also called snap button, press button, press stud, press fastener, dome fastener, popper, snap and tich, is a pair of interlocking discs, made out of a metal or plastic, commonly used in place of traditional buttons to fasten clothing and for similar purposes. A circular lip under one disc fits into a groove on the top of the other, holding them fast until a certain amount of force is applied. Different types of snaps can be attached to fabric or leather by riveting with a punch and die set specific to the type of rivet snaps used, sewing, or plying with special snap pliers.