A dropped ceiling is a secondary ceiling, hung below the main (structural) ceiling. It may also be referred to as a drop ceiling, T-bar ceiling, false ceiling, suspended ceiling, grid ceiling, drop in ceiling, drop out ceiling, or ceiling tiles and is a staple of modern construction and architecture in both residential and commercial applications. It is used by a building designer to provide Aesthetics, Service void, Acoustic control, Thermal insulation, Fire protection, Ventilation and Lighting.