Semiotics

Semiotics

Semiotics is the study of signs, in this could also come the study of metaphor, symbolism, significance and communication.
Signs are used all over the world to indicate where or what something is, the best way to explain a semiotic sign is to show one. 

This is a sign to signify a disabled person. If put in the an appropriate place such as a toilet or parking bay, people will know that this is specifically for disabled people. A sign like this is more likely to be used that the words 'Disabled' because an image is universal, no matter what age or race, a person is very likely to understand what this sign will mean.
The study of signs, or semiotics has been around for hundreds of years, the philosopher Charles Sanders Pierce once quoted that "we only think in signs", meaning that the human brain will only understand something when it is in the form of a sign, be in text, image, acts or objects.

This image is the easiest way of describing a semiotic sign. Here we have a drawing of a tree (object), then we have the interpretant (what we know a tree to be), then we have the representment, the word tree.

This applies in most things we come across in our daily lives to help people all over the world to understand the same things.

http://www.brianschrank.com/Intro_to_Media_Studies/resources/semiotics%20for%20beginners/index.html