For more than 150 years, new communications technologies have tended to concentrate and commercialize the production and exchange of information, while extending the geographic and social reach of information distribution networks. High-volume mechanical presses and the telegraph combined with new business practices to change newspapers from small-circulation local efforts into mass media. Newspapers became means of communications intended to reach ever-larger and more dispersed audiences, and their management required substantial capital investment. As the size of the audience and its geographic and social dispersion increased, public discourse developed an increasingly one-way model. Information and opinion that was widely known and formed the shared basis for political conversation and broad social relations flowed from ever more capital-intensive commercial and professional producers to passive, undifferentiated consumers. It was a model easily adopted and amplified by radio, television, and later cable and satellite communications.----------------------
-------------- The economics of long-distance mass distribution systems necessary to reach this constantly increasing and more dispersed relevant population were typified by high up-front costs and low marginal costs of distribution. These cost characteristics drove cultural production toward delivery to ever-wider audiences of increasingly high production-value goods, whose fixed costs could be spread over ever-larger audiences-like television series, recorded music, and movies. Because of these economic characteristics, the mass-media model of information and cultural production and transmission became the dominant form of public communication in the twentieth century.