The Mathematical Theory of Communication

Thus any limitations discovered in the theory at Level A necessarily apply to levels B and C.

he indicated how very explicit, operationally significant concepts such as the information content of a source or the information capacity of a channel can be identified using entropy and maximization of functions involving entropy.

“the semantic aspects of communication are irrelevant to the engineering aspects.”

Ergodic systems, in other words, exhibit a particularly safe and comforting sort of statistical regularity.

A system which produces a sequence of symbols (which may, of course, be letters or musical notes, say, rather than words) according to certain probabilities is called a stochastic process,

The concept of information applies not to the individual messages (as the concept of meaning would), but rather to the situation as a whole, the unit information indicating that in this situation one has an amount of freedom of choice, in selecting a message, which it is convenient to regard as a standard or unit amount.

with any reasonably broad definition of conduct, it is clear that communication either affects conduct or is without any discernible and probable effect at all.

In particular, information must not be confused with meaning.

The notion that a channel has a specific information capacity, which can be measured in bits per second, has had a profound influence.