The presentation layer

While it may sound like a way of visually representing the data, the presentation layer is actually a way of defining how the data is to be interpreted by any consumer that wants to look at it. This layer provides context for application-layer entities from different hosts to mutually interact with a PDU. Entities in the presentation layer are responsible for describing how data passed from the application layer should be interpreted on the other side of a given data transaction. It does the work of abstracting away the encoding or serialization of PDUs from the higher-level business logic of application layer entities.