1. Marshall McLuhan was a Canadian professor who argued that new technologies have social and psychological impacts beyond their intended uses or functions. He believed that "the medium is the message" in that a technology's effects come from its characteristics as a medium.
2. McLuhan proposed that machines extend human abilities but also accelerate and amplify existing human processes. The nature of each new technology brings about changes in scale and patterns of thought.
3. A review of McLuhan's work argues that he took a nuanced, "humanist technologist" perspective in exploring how technological change shapes human agency, and that his theories remain relevant if considered in their full historical context rather than through isolated quotes.