Two-step flow of communication
Two-step flow model was propouded by Paul Lazarsfeld and Elihu Katz. Unlike the hypodermic needle model which considers mass media effects to be direct, the two-step flow model stresses human agency.According to Lazarsfeld and Katz, mass media information is channeled to the "massess" through opinion leadership. The people with most access to media, and having a more literate understanding of media content, explain and diffuse the content to others.
Two-step flow model laid the foundation for diffusion of innovations.






