That part of a
communication chain in which signals are transmitted from a sender to a receiver. Unlike other processes in a communication chain (e.g.,
encoding, decoding ,
translation ,
transformation ), a channel involves a single physical medium that spans the difference in time and in space which separates senders from receivers. A
memory is that special case of a channel in which the sender transmits signals to himself at a later point in time. A channel is characterized by the physical properties of its medium and imposes a
constraint on the capacity for communication: (1) its selective capability to store, retain, and transmit certain kinds of signals, (2) its sensitivity to non-systematic distortions and decay (
see noise, equivocation ,
redundancy ) and (3) its capacity to transmit
information. Primary channels in unaided human communication are audio (largely verbal and musical), visual (largely non-verbal and
icon ic) and tactile. In modern society channels are differentiated mainly by the technical devices used, e.g., writing, printing, telephone, photography, television (video and audio channels), satellite communication,
computer networks. Each has its own limitations and properties. It is well established that the social reliance on particular channels of communication profoundly influences how a society administers itself, develops and expands. (
Krippendorff )
