In Section 2, we recall the results from classical information theory that are needed by the rest of this publication.
We present them with proofs, because the proofs are short, help reading the novel results in subsequent sections, and, unlike classical information theory, we also consider multiple representations of the same object.
In classical information theory, objects are represented by bit strings that are self-delimiting or, more generally, whose system is uniquely decodable.
We will soon see that in classical information theory, if an object has more than one representation, then the representation system is not memory-optimal.
It says that in classical information theory, and more generally in any theory that allows the use of self-delimiting bit strings as representations, Kraft s inequality is as tight as it could be.