Symbolic representations can be defined by usual terms based on the various languages we use to communicate our experiences, our knowledge and general data: written or spoken language, graphic representations, iconic and photographic cues, etc. which all deal with various semiotic and symbolic forms. To clarify this notion, we could refer to a well known example taken from Glass and Holoak, quoted in Denis (1989). The drawing of a cup can be represented by its verbal definition or by a more or less complex mathematical expression: the cup can be described by an elliptic paraboloidal equation and the saucer by a circle equation. As far as we are concerned, we would gladly add that the drawing of the cup already constitutes an analogue representation of the object, the cup itself... With these definition in hand, we have three different representation of the 'object cup' available: a drawing, a verbal definition and mathematical equations.
With broadcasting and delivery of data and knowledge, on the contrary, we deal with transmission channels and technical/material devices used by the recipient to take over the message. Finally, the reception environment can be understood in view of the following four different points of view: physical, material, institutional and socio-cultural. The distinction between media and representation we are presenting here is not new. In 1969 already, authors like Tosti and Ball (quoted in Heidt, 1981) asserted that the main learning factor was not the medium itself but rather the way knowledge is arranged and delivered.
and/or technical vectors of transmission and broadcast: air conduction, radio
waves, wire technology, etc. as well as additional device for
encoding/decoding. Note that the channel can determine actual material
reception conditions as is the case for subdued light required for movie
device for information storage : magnetic tape, optical disk, floppies, hard
device used to become aware of the actual representation: paper technology,
projection screens, computer monitors, etc. A technical object allowing a
strict restitution, the so-called 'display function'.
social interaction scene, the material, human, institutional and socio-cultural
frame of reference.
of representation :
of representation, 'languages', whether through arbitrary signs (verbal
language, mathematical formula) or through various analogue signs and signals
rooted in a resemblance relation with the object (photographs, graphics,
Let us take an example to further explain these distinctions. The photographic representation of an animal, like a dromedary, may be shown as a photography, printed on positive paper, or may be shown on screen through a film, a positive transparency, or may even be digitally scanned and displayed on a computer monitor. In all three cases, the representation, the symbolic form, is identical, while the medium is very different indeed. As representations, all three instances show a photographic image, with its distinctive traits. As a semiotic form, a photography is an 'icon', distinct from a verbal representation using words, i.e. a representation that strongly resembles what it represents. The photo of this dromedary resembles an animal that I know through its rendering on a famous cigarette packet, Camel, through my childhood circus memories, through my trips in Africa, etc. This material representation is well in accordance with the prototype image I extract from my various previous former experiences. It may therefore appear to be similar to the animal itself. What distinguishes the three cases at hand is that the actual presentation means and the conditions of perception and/or reception of the message are completely different. In the first case, the image is meant to be read by an individual. In the second case, it is watched collectively, in subdued light. In the third case, we have an object that can be treated in many ways, possible only with digital computerised graphic material.
Consequently, we ought to modulate Tosti's and Ball's thesis since we today know that photography, as we have described it above, undergoes a process of deciphering by the viewer in which his apprehension and interpretation changes with medium used and in relation with the conditions of reception. These conditions play an essential role together with the influence of the channel on viewing. Hence, understanding a message means to account for all these elements: is a given film seen on TV or watched in the local theatre really the same film ? It is clearly in the light of this kind of observation that the well-known Mac Luhan motto is to be understood: "The medium is the message" (1967).
 Let's recall that the English Open University, often taken as a model for subsequent distance universities, was first named University of the Airs. This name was later adopted by quite a number of other institutions, e.g. by the College of the Air of Mauritius
 We could say "uses carrying meaning" here. A concept very much in use in the '70s that seems to have lost much of its interest nowadays. Perhaps because is it still carrying too many hidden political and ideological overtones. In spite of this, since this idea integrates the production of meaning and signification into the framework of social practice, it has not lost any of its appropriateness
 Funnily enough, the image used by the Camel brand of cigarettes is in fact the dromedary "a camel of unusual speed bred and [...] trained for riding" (Webster, New Collegiate Dictionary, C. & C. Merriam Co, 1979).