Semiotics is the study of signs. In a class lecture, Kevin Williams,PhD explained semiotics as a formal system of communication, a methodology. He also explained the word, "semiotics" derives from the Greek word "semata" meaning road sign. The basic themes for semiotics are signs and codes.
Signs are indicators. A road sign, for example, indicates direction; however, it does not describe the road. Dr. Williams also described the different theories behind signs: Plato said words are representation of something. Plato believed signs= a signifier (a physical thing such as a dog) + a signified (the ideal thing such as the image of our own dog or our neighbors dog, or a puppy foot print). In"Semiotics the basics" by Daniel Chandler, Saussure also, "defined a sign as being composed of a 'signifier' and a 'signified'." The difference is Saussure said signs= a chain of signifies and that words are only connected to other words. Charles Peirce also coined a theory of semiotics he said a sign is anything that points to something else. He was specifically interested in the connection between the signified and the signifier. He divided signs into three groups: symbols, indexes, and icons.
In "Semiotics the basics," "'code' is central in structuralist semiotics... Codes organize signs into meaningful systems which correlate signifies and signified."
Signs present a symbol of information, and codes allow us to interpret the meaning of the sign appropriate for a given environment. A stop sign, for example, indicates that you should stop; the general understanding in a society that grants the sign the power to indicate the need to stop is code. Another example is money. A dollar bill is a sign of $1.00 worth of money, it is a mutual agreement, or a code among society that allows that piece of fine cloth to be a sign of $1.00. Hence, without signs and codes it would be impossible to communicate with one another. None of our actions would have meaning if there was not an understanding of a given sign.
This is especially important in the age of electronic-communication because we communicate person-to-person less often. We have a much broader need to use signs and codes since all electronic communication is sign: every letter we type, every movie we watch, every text message we send is sign.
