The basic unit of interest for semiotics. It is perhaps best apprehended as a unit of meaning whose principal point of distinction is the fact that it is not meaningful in itself, but is only ever a sign of (or pointer to) a theoretically ‘full’ meaning that lies elsewhere. Although the two principal ‘fathers’ of semiotics, Saussure, Ferdinand de and Peirce, Charles Sanders, did not agree on whether the sign is a binary or tertiary construct, their independently arrived at conceptions of the sign nonetheless share a number of key features. The sign is composed of two or three inter-related and interactive parts which are distinct from one another but inseparable. For Saussure, the sign consists of a signifier and a signified---the former is the distinctive acoustic image (the ‘c’ sound in ‘cat’, for instance, which sounds very different from the ‘t’ sound in the same word), while the latter is the mental concept we arbitrarily associate with that sound (i.e. not an actual cat, but the idea of a cat). For Peirce, the sign consists of the representamen, the interpretant, and the object---the representamen is the perceptible object (or what is also known as the sign vehicle), the interpretant is the meaning or the effect of the sign, while the object is that which the sign represents. In both cases, too, the sign is greater than its constituent material vehicle (e.g. the colour red in a traffic light is only one part of the semiotic signal drivers use to know when to stop); it is not identical with its material vehicle (i.e. the colour red is not in and of itself a sign); nor is it identical with its elements (i.e. the colour red is only one part of the sign).