Viacom, Inc. (short for Video & Audio Communications) is an American global mass media company with interests primarily in cinema and cable television. It is the world's sixth largest broadcasting and cable company in terms of revenue (behind Comcast, The Walt Disney Company, Twenty-First Century Fox, Inc., Time Warner, and CBS Corporation, respectively). Voting control of Viacom is held by National Amusements, Inc., a privately owned theater company controlled by billionaire Sumner Redstone. Redstone also holds, via National Amusements, a controlling stake in CBS Corporation.