This document discusses key concepts related to mass communication including definitions, components, and functions. It defines mass communication as using mass media to send messages to large audiences to inform, entertain, or persuade. The key components it identifies are mass communicators, mass messages, mass media, mass communication, and mass audiences. It describes mass communicators as those who produce messages for mass media like journalists and advertisers. Mass messages are the content like news, movies, songs, etc. Mass media are the vehicles that carry these messages like newspapers, TV, radio, etc. It also discusses the size and diversity of mass audiences. Finally, it outlines several functions of mass communication including providing information, reflecting cultural values, entertainment, and mobilizing