NONORAL LANGUAGE Language, although primarily oral, can also be represented in other media, such as writing. Under certain circumstances, spoken language can be supplanted by other media, as in sign language among the deaf (see Sign Language). Writing can be viewed in one sense as a more permanent physical record of the spoken language. However, written and spoken languages tend to diverge from one another, partly because of the difference in medium. In spoken language, the structure of a message cannot be too complex because of the risk that the listener will misunderstand the message. Since the communication is face-to-face, however, the speaker has the opportunity to receive feedback from the listener and to clarify what the listener does not understand. Sentence structures in written communication can be more complex because readers can return to an earlier part of the text to clarify their understanding. However, the writer usually does not have the opportunity to receive feedback from the reader and to rework the text, so texts must be written with greater clarity. An example of this difference between written and spoken language is found in languages that have only recently developed written variants. In the written variants there is a rapid increase in the use of words such as because and however in order to make explicit links between sentences—links that are normally left implicit in spoken language.

Sign languages, which differ from signed versions of spoken languages, are the native languages of most members of deaf communities. Linguists have only recently begun to appreciate the levels of complexity and expressiveness found in sign languages. In particular, as in oral languages, sign languages are generally arbitrary in their use of signs: In general, no reason exists, other than convention, for a certain sign to have a particular meaning. Sign languages also exhibit dual patterning, in which a small number of components combine to produce the total range of signs, similar to the way in which letters combine to make words in English. In addition, sign languages use complex syntax and can discuss the same wide range of topics possible in spoken languages.

Body language refers to the conveying of messages through body movements other than those movements that form a part of sign or spoken languages. Some gestures can have quite specific meanings, such as those for saying good-bye or for asking someone to approach. Other gestures more generally accompany speech, such as those used to emphasize a particular point. Although there are cross-cultural similarities in body language, substantial differences also exist both in the extent to which body language is used and in the interpretations given to particular instances of body language. For example, the head gestures for “yes” and “no” used in the Balkans seem inverted to other Europeans. Also, the physical distance kept between participants in a conversation varies from culture to culture: A distance considered normal in one culture can strike someone from another culture as aggressively close.

In certain circumstances, other media can be used to convey linguistic messages, particularly when normal media are unavailable. For example, Morse code directly encodes a written message, letter by letter, so that it can be transmitted by a medium that allows only two values—traditionally, short and long signals or dots and dashes (see Morse Code, International). Drums can be used to convey messages over distances beyond the human voice's reach—a method known as drum talk. In some cases, such communication methods serve the function of keeping a message secret from the uninitiated. This is often the case with whistle speech, a form of communication in which whistling substitutes for regular speech, usually used for communication over distances.