"Media language refers to the ways in which media producers make meaning"
What this means is: how we read meaning in film. For example, we know a film is a Western before the action has even begun by the cowboy hats worn of the ranch setting. We know it's a horror film because of the music used and the dark lighting. These aspects of communication allow us to read the language of the film and subconsciously we categorise it accordingly.
Codes and Conventions
Genre plays a key part of media language. We know what to expect when we watch a romance and those codes and conventions being met allows us to read the language of that particular film. Things become harder for us to read when codes are broken; this would normally be for a reason though, for example in case a thriller meant to unsettle its audience to throw them off scent.
Code - 'Secret codes' are information that we ascertain from the media product, that we decode to understand the 'hidden' meaning.
Convention - The aspects of a particular genre that it relies on; for a horror, this might be a villain, a victim and scary moments.
Narrative
Narrative structures also plays a part in film language. We expect media products to have fully rounded narrative structures; this allows us to understand when a film is finished and when there is more to come. Think of the horror film where the baddie comes back to life for one more attack - we expect this to happen as it happens too frequently so we begin to read the films language.
Mise En Scene
The mise en scene of a film tells us as an audience exactly what we need to know immediately; where we are, when we exist, what the genre is. Mise en scene is the most obvious form of communication a director or producer has to offer us clear messages of how we are to consume that product.
Representation
Representation allows the audience to make decisions about the media product on their own. They are placed by the producers to inform the audience but they will have different connotations for each individual. Again, this is how language is passed from producer to audience.