A drawing pin (in British English) or [thumb] tack (in North American English), also called a push-pin, is a short, small pin or nail with a flat, broad head that can be pressed into place with pressure from the thumb, often used for hanging light articles on a wall or noticeboard.
Thumb tacks made of brass, tin or iron may be referred to as brass tacks, brass pins, tin tacks or iron tacks, respectively.[1] These terms are particularly used in the idiomatic expression to come (or get) down to brass (or otherwise) tacks, meaning to consider basic facts of a situation.[2]