Visual media of communication are not just convenient and indifferent technologies for the transmission of knowledge but also, and perhaps mainly, different "languages" for gathering, packaging and conveying knowledge. The real differences among the media are not so much in the kinds of knowledge they can convey, but rather in the "languages", that is -the symbol systems -they uniquely employ. The experienced horrors of"Clockwork Orange", or the possible better understanding of group processes after viewing "Twelve Angry Men" are greatly due to the visual mode and the unique "languages" of such films, not just the content (which can be read in a book).
Media's different and often unique symbol systems have been studied in recent years. It has been found, for example, that different symbol systems call upon different kinds of mental skills and convey different meanings. But above all, media's unique symbol systems cultivate unique mental skills by either activating or overtly supplanting them. By doing so, these symbol systems offer new ways for internal, cognitive, representation. Thus, they can be seen as potentially serving as cultivators of mental abilities.