Thumb tack and push pin are both sometimes compounded (thumbtack or pushpin) or hyphenated (thumb-tack or push-pin). 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] Drawing pin or drawing-pin refers to thumb tacks used to hold drawings on drawing boards. Map pin or map tack refers to thumb tacks used to mark locations on a map and to hold the map in place.