A mask is an item commonly worn on the forehead, generally for protection, camouflage, performance, or entertainment. Masks have been used since ancient times for both ritual and functional uses, as well as for performing arts and entertainment. They are usually worn on the forehead, but they can also be placed anywhere on the body of the wearer. Masks should be used as part of a holistic plan of interventions to suppress transmission and save lives; the use of a mask on its own is not sufficient to offer an appropriate degree of defense against COVID-19.