Barthes

Roland Barthes theorised that narrative texts could be ‘decoded’ in different ways, and that multiple different meanings  could be obtained from the same text, depending on how it was ‘read’.

Texts fall into two categories:

OPEN – the text can be viewed and unpicked in multiple different ways. There are several interpretations of what the text means, including ones that contradict each other.
CLOSED – there is only one way of viewing the text. The message is so clear and obvious that to try and find a different meaning than the one presented is either very difficult or just illogical.

There are 5 codes that Barthes argues can be used to interpret any text. They are the following:

Hermeneutic Code: the mysteries of the text
Clues are dropped in the text, but no clear answers are given. By providing questions (enigmas) but not the answers, the narrative compels the audience to want to know more. However, enigmas that go unanswered can frustrate the audience or come across as pointless. For a recent example of this, think about the enigma created around the identity Rey’s parents in Star Wars Episode 7: The Force Awakens. The answering of this enigma in Star Wars Episode 8: The Last Jedi was seen by a section of the audience to be unsatisfying, rendering the original mystery pointless.

Proairetic Code: the narrative drive of the text
This code involves the inclusion of action sequences to drive the narrative forward. Action in whatever form it takes usually revolves around unresolved conflict, which can add suspense to the text.

Semantic Code: the resonances of the text
This code involves any part of the text that suggests deeper or additional meaning to that on the surface of the text. This could take the form of an allegory or parable, whereby the entire film itself functions as a symbol of something else. An example of this would be how Mother! retells the story of the Bible from creation to crucifixion, wrapped up inside an entirely different setting.

Symbolic Code: the symbolic structure of the text
This code takes the same elements as the Semantic Code and reflects it on as smaller scale. For example: Russel is missing one badge from his sash in Up which is located over his heart, while also pining for a father figure in his life is more than coincidence. Carl becoming his father figure and ending the film by pinning a badge in the sash’s empty space completes this metaphor.

Cultural Code: the background knowledge of the text
This code refers to anything in the text that connects with an external body of knowledge held by the audience; for example cultural, scientific or historical knowledge.

An explanation of each code in more detail can be found here.