Ask any visual communication student/researcher about clear distinctions between the seemingly synonymous, yet realistically two very individualistic words (or rather conceptions about) - SIGN and SIGNAGE - the descriptions are generally ambiguous. Often this confusion amongst students, researchers, practitioners and faculty teaching sign design is understandable. The foremost reason being, that both the terms SIGN and SIGNAGE share the four letter word SIGN as a common binding concept.
As a researcher in the area of sign design, this ambiguity needs to be solved. There has to be a concrete and identifiable distinction between the two terms. However, in the context of the science of signs (Semiotics / Semiology), we'll see that somewhere this distinction gets blurred.
Giving all due respect to the historical roots, 'signs' have been the most fundamental elements since 18,000 B.C. signifying the Paleolithic Age of Cave paintings. They were not only the means of human to human discourse, but were a marquee of spiritual and ritualistic concepts in nature symbolism. Slowly, as man progressed from the primitive state to the civilized nature of his world, these 'signs' assumed more roles and functions in different spheres of human living and the world. Therefore, a visible division of the land in form of continents, countries, states within the countries, cities, districts, locales, villages and towns sprang up as a result of scientific, historical, social, cultural, economic, political etc. development of human mind and intelligence to create systems out of tangible and intangible sources from nature and its surroundings. With humans inventing objects, building shelters, constructing cities, thinking about concepts, ideas, methods with their constantly evolving cognitive and intutive faculties of mind also developed smaller, functional entities that are all various forms or kinds of signs. They are the diverse modes given to human expression(s) that help establish an evolving interface between the human instinct to search, know and experience world around. This beauty in diversity has various forms - be it symbols, icons, indices, metaphors, ideas, gestures (the holistic forms); and also the present day billboards, posters, labels, placards, kiosks, banners and signage (the practical/ functional and tangible forms that aid humans to navigate easily and find their way in built spaces and environments).
So, can we say that 'signs' formulate the larger 'paradigm' or the 'ground' to carry all smaller entities. And, amongst these functional forms, 'signage' is one of the most significant requirements in terms of creating 'interactive' discourses that require the presence of a certain profile of audience. However, from the Semiosis of 'signs', it is apparent, that the discourse happens (be it interactive or not, meaning that the presence of an audience is not mandatory). This makes everything and everybody, so on and so forth a 'sign'. Therefore, 'sign' was defined by Ferdinand de Saussure in one of the most versatile and open to discussion way. The definition being -
" A sign is something which stands to somebody for something in some respect or capacity. It addresses somebody, that is creates in the mind of that person an equivalent sign, or perhaps a more developed sign. The sign which it creates I call the interpretant of the first sign. The sign stands for something, its object."
'The Betrayal of Images' by Rene Magritte 
As goes for the term 'Signage', the term first came into existence in 1972. Its etymology refers to road signs or signs outside stores, coming from from sign (n.) + -age.
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Copyright: Nanki Nath