Television differs in several ways from books that may affect cognitive structures and processes. As with books, television can employ pictures, diagrams, and other representational symbol systems but in TV these symbols are transient and able to depict motion. While linguistic information in television can be orthographic, more often it is oral and, as with audiotape and radio, transient. Because in television, linguistic and pictorial symbol systems are transient and because they are presented simultaneously, it is possible that viewers process this information in a very different way than the back- and-forth serial processing of linguistic and representational information in books. It is also possible that the symbol systems used and their transient nature affects the mental representations created with television.