A doormat or door-mat is a flat, usually rectangular, object placed immediately outside or inside the entrance to a house or other building, to allow people to easily scrub or wipe the soles of their shoes before entering. Doormats are usually made from tough, long-lasting material such as coir, palmyra (palm) fibres and stalks, nylon, rubber, cloth, or aluminium and other metals. A doormat may also be known as a welcome mat, as its location at an entrance constitutes a "welcome" to visitors, and may therefore also bear some word, message or sign of greeting.
A whistle is an instrument which produces sound from a stream of gas, most commonly air. It may be mouth-operated, or powered by air pressure, steam, or other means.
