Salience

In semiotics, modality refers to the particular way in which the information is to be encoded for presentation to humans, i.e. to the type of sign and to the status of reality ascribed to or claimed by a sign, text or genre. It is more closely associated with the semiotics of Charles Peirce (1839-1914) than Saussure (1857-1913) because meaning is conceived as an effect of a set of signs. In the Peircian model, a reference is made to an object when the sign-carrier (a representamen) is interpreted recursively by another sign (becoming its interpretant), a conception of meaning that does in fact imply a classification of sign types.

Discussion of sign-type
The psychology of perception seems to suggest the existence of a common cognitive system which treats all or most sensorily conveyed meanings in the same way. If all signs must also be objects of perception, there is every reason to believe that their modality will determine at least part of their nature. Thus, the sensory modalities will be visual, auditory, tactile, olfactory, kinetic, etc. A list of sign types would include: text, symbol, index, image, map, graph, diagram, etc. Some combinations of signs can be multi-modal, i.e. different types of signs grouped together for effect. But the distinction between a medium and a modality should be clarified: So, the modality refers to a certain type of information and/or the representation format in which information is stored. The medium is the means whereby this information is delivered to the senses of the interpreter. Natural language is the primary modality, having many invariant properties across the auditory media as spoken language, the visual media as written language, the tactile media as Braille, and kinetic media as sign language. When meaning is conveyed by spoken language, it is converted into sound waves broadcast by the speaker and received by another's ears. Yet this stimulus cannot be divorced from the visual evidence of the speaker's manner and gestures, and the general awareness of the physical location and its possible connotative significance. Similarly, meaning that is contained in a visual form cannot be divorced from the iconicity and implications of the form. If handwritten, is the writing neat or does it evidence emotion in its style. What type of paper is used, what colour ink, what kind of writing instrument: all such questions are relevant to an interpretation of the significance of what is represented. But images are distinguishable from natural language. For Roland Barthes (1915-80), language functions with relatively determinate meanings whereas images "say" nothing. Nevertheless, there is a rhetoric for arranging the parts which are to signify, and an emerging, if not yet generally accepted, syntax that articulates their parts and binds them into an effective whole.
 * text is a medium for presenting the modality of natural language;
 * image is both a medium and a modality;
 * music is a modality for the auditory media.

Discussion of reality status
When interpreting a system of signs, the audience will make a judgement about the modality of the whole, i.e. they will decide whether it is more likely to be fact or fiction, real or unreal. It also refers to how the audience feels about the message's validity and reliability. Images with higher modality appear more real than those with a lesser modality. To make this calibration, the audience will draw on its collective experience and understanding of the real world and of the particular medium of communication being used. Hence, those who enter a cineplex or theatre are aware that the content of the system they are about to view will usually be delivered by actors. But, if an individual randomly switches channel on the television, the new set of signifers must be evaluated: does this appear to be live or recorded, are these people known to be actors or do they have real-world roles that would explain their presence on the television, what does the genre or format of the programme appear to be, etc? If a provisional assessment is made that real events are being depicted, the more detailed credibility or plausibility can be evaluated by reference to the viewer's narrative sense. Has the viewer personal or vicarious experience of this type of event? Is this how real people would be expected to react and, say, explain their motives? This form of analysis to determine possibility and familiarity, whether conscious or unconscious, enables the audience to assess the authority of the speakers and the reliability of their message. Thus, the audience might believe what a person says in an interview because it matches their own experience. What happens in a soap opera may be emotionally involving because, although fictional, it represents real world situations.