Marshall McLuhan

Canadian media theorist who argued that the form of a medium — not its content — shapes human consciousness and social organization, producing the most influential theory of media in the 20th century.

The medium is the message: a medium's effects arise from its form, not its content — television creates different cognitive habits than print regardless of what is televised. Hot vs. cool media: hot media (radio, film) are high in one sense and require little participation; cool media (TV, telephone) are low in definition and require high participation. The global village: electronic media collapse distance and create a new tribal consciousness. Understanding Media: the defining text of media theory.