Icons, Indexes and Symbols

-An Icon has a physical resemblance to the signified, the thing being represented. A photograph is a good example as it certainly resembles whatever it depicts.

-An Index shows evidence of what’s being represented. A good example is using an image of smoke to indicate fire.

-A Symbol has no resemblance between the signifier and the signified. The connection between them must be culturally learned. Numbers and alphabets are good examples. There’s nothing inherent in the number 9 to indicate what it represents. It must be culturally learned.

E.g.


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It is important to note that overlap between the categories is inevitable and the theory's basis is more sociological than scientific.