For the “message” of any medium or technology is the change of scale or pace or pattern that it introduces into human affairs. The railway did not introduce movement in transportation or wheel or road into human society but it accelerated and enlarged the scale of previous human functions, creating totally new kinds of cities and new kinds of work and leisure. This happened whether the railway functioned in a tropical or a northern environment, and is quite independent of the freight or content of the railway medium. The airplane on the other hand, by accelerating the rate of transportation, tends to dissolve the railway form of city, politics, and association, quite independently of what the airplane is used for.
Marshall McLuhan, 1967, The Medium is the Message, An Inventory of Effects