Once the breakdown of the thematics is completed,37 there follows the stage of its “codification”: choosing the best channel of communication for each theme and its representation. A codification may be simple or compound. The former utilizes either the visual (pictorial or graphic), the tactile, or the auditive channel; the latter utilizes various channels.38 The selection of the pictorial or graphic channel depends not only on the material to be codified, but also on whether or not the individuals with whom one wishes to communicate are literate.