 Most of the theories of broadly semantic information outlined in  section 2  appeal to information channels in one sense or another (with a channel being a relation allowing information the flow from one state to another). In  section 3  we will look at theories of information channels directly. (For a detailed examination of the formal properties of the theory of information channels, as well as how it is that the theory connects with other issues in logic and information more generally, see the entry on  logic and information.)  We will see how the original theory of information channels due to Barwise and Perry emerged from Austin’s theory of semantic content, as well as how it is that the theory of information channels has been developed and extended in order to give a semantics for information flow itself, as well as informational semantics for natural language fragments and epistemic phenomena.