Codes can be divided into two different catagories, technical and symbolic. These are codes are a system of signs which create meaning within the adverts.
Technical codes are ways that the equipment is used to tell the story the advert is trying to get across, for example the camera work. The camera angle, shots, iconography, editing, lighting, sound, music, computer graphics and special effects.
Symbolic codes use language, dress and actions of characters to get the message across. These type of codes are used to show more in depth of the advert, for example the characters actions will show how they are feeling.
Some codes fit both, for example music is technical but is also symbolic.
Codes can create feelings to the audience through effects and techniques, for example dull / rainy weather in a film and a woman looking upset can make the audience feel bad for the woman and sometimes show emotion.
Conventions
Conventions are accepted ways of doing something. They're what you expect to see in a certain genre, for example for a shampoo advert you would expect to see the woman washing her hair or if not then showing off her hair close up in the shots.
Adverts are mostly always the same length of time and the brand / slogan get shown at the end.
Case Study: Herbal Essences Shampoo
Shampoo adverts use very clear and similar codes and conventions, they develop over the years as you can see in these adverts from past years to today.
For example, close up of the hair, model moving the hair, hair being washed using the shampoo that's being advertised, the model always looks happy, the product being shown, scientific facts about the product, the slogan gets used a lot also.