A bolster is a long narrow pillow or cushion filled with cotton, down or fibre. Bolsters are usually firm for back or arm support or for decorative application. They are not a standard size or shape and commonly have a zipper or hook-and-loop enclosure. A foam insert is sometimes used for additional support. A bolster is also referred to as a cushion, a pillow and a prop. In western countries, a bolster is usually placed at the head of one's bed and functions as head or lower back support, or as an arm support on furniture with high rigid sides. Bolster pillows are also used as bumpers in cribs and for lounging on the floor in family and children's rooms.