Playa, the Spanish word for beach or shore, is a term used to describe the dry lakebeds of the American desert. A playa is a hydrologically closed system, with no water outsource, so all water entering the flat is eventually lost through evaporation. For much of the year Playas can contain a 3-5 inch layer of water from rain or mountain runoff, this water evaporates slowly depositing an alkaline or salt flat. The thin layer of water and ice polishes the surface creating some of the flattest and smoothest land planes on earth, later the sun bakes this surface to the consistency of concrete. The playa is the ideal plane for use in land speed car racing, military landing strips, and also has been used extensively as the abstract backdrops of fashion shoots and car commercials.