Signage systems are visually oriented information systems, consisting of signs, maps, arrows, color-codings systems, pictograms and different typographic elements. Signage systems differ from other methods of information presentation because they are typically used to guide people's passage through the physical world; road signs on a highway, station identification signs in a subway and overhead signs in an airport are all common examples of signage systems. The act of following a signage system is known as wayfinding, waysigning or signposting.

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While any collection of correlated signs can be considered a signage system, the term is typically used to refer to a group of signs with a coherent design and purpose. Frequently, significant effort is put into creating an intelligent presentation for a sign that takes into account scientific knowledge about humans' reactive capabilities to typefaces and colors. This research has produced a design aesthetic of certain fonts that are frequently used (especially humanist sans-serif designs like Frutiger, which was created in 1969 for signage in Paris' Charles de Gaulle Airport.)

The dictionary definition of sign at Wiktionary