Definitions
icon
sign/symbol
metaphor

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Reference

Sign and Symbol

A. Marcus, 1992, Graphic Design for Electronic Documents and User Interfaces, ACM Press, New York, p.52.

J. Foley, 1993, The Guinness Encyclopaedia of Signs and Symbols, Guinness, p.9.

What needs definition is the relationship between sign and symbol. When describing a sign Adrian Frutiger writes that 'the illustrative intention is abandoned in the process of converting the picture into a sign'. Foley describes a sign as 'principally any conventional graphic mark used to convey a specific meaning'. There are three kinds of sign - those which look like what they represent, abstract forms which represent the essence of an object, and indexical signs where the referent sign implies its meaning through an indirect relationship with what it represents.

Aaron Marcus describes a 'trail of muddy footsteps in a front hallway' as an index sign that children have entered the house, because it is a regular occurrence and they are always being told to take off their shoes, so they are the logical cause' (Marcus, 1992). But the meaning of a sign can become a symbol. The dividing line between the two is when sign attributes are raised to symbolise a deeper meaning, which Foley describes as 'something that stands for, represents, or denotes something else, particularly some tangible object representing something intangible or abstract.

Such as an idea or concept (as for example the owl, or its depiction, as wisdom)' (Foley, 1993). A symbol can also contain many sign elements within the compound symbol to convey further meaning, or be arbitrary in its appearance, and does not necessarily need to have its connotation understood. It's meaning is through learning. Compound icons used on computer interfaces might therefore have some of the qualities attributed to a sign or a symbol, but should primarily look like the function it represents.

Sign - specific meaning such as public signs.

Symbol - Derlite manufacture spark ignition electrodes. The connotation is in the colour and the sparks.