What is the difference between mediated and mass communication?

Mass communication includes messages sent to large, public, dissimilar, anonymous, distant audiences using some intermediate instrument of transfer. The instruments include electronic (for example, radio, television, tape, and film) and print (for example, newspaper, magazine, book, pamphlet, brochure, direct-mail campaign). The "mass media," as they are often called, have grown to include the print media of books, newspapers and magazines, the electronic media of television, radio, and audio/video recording, and the new media of computers and computer networks. Mediated communication occurs when two (or a few) people use some intermediate means for carrying their messages. They do not communicate face to face and thus do not have direct feedback. Mediated communication often uses a mechanical or electrical device to transmit or receive messages. Examples include the telephone, closed-circuit television, radio, radar, and the communication satellite. Mediated communication also occurs through letters, reports, forms, and interoffice memoranda.