The document discusses the hypodermic needle theory of mass communication, which suggests that media messages are directly injected into passive audiences, immediately influencing them. It notes that this theory from the 1930s is now considered outdated. The two-step flow model is presented as an alternative, in which opinion leaders influence the public rather than direct media effects. Lasswell's communication formula is also described as analyzing the basic questions of who communicates what through which channel to whom with what effect.