A drawing pin (British English) or thumb tack (North American English) is a short nail or pin used to fasten items to a wall or board for display and intended to be inserted by hand, usually using the thumb. A variety of names are used to refer to different designs intended for various purposes. Thumb tacks made of brass, tin or iron may be referred to as brass tacks, brass pins, tin tacks or iron tacks, respectively.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.