All animals, including ourselves, communicate by exchanging nonverbal signs. Verbal signs - that is, language - evolved uniquely in the genus Homo and seems first to have been present in a hominid species named habilis ("handy man") which flourished about 2.4 to 1.5 million years ago. This form was swiftly followed by Homo erectus ("upright man"), dated about 1.5 millions years ago, and soon by at least two subspecies, of which solely a descendant of our own kind, Homo sapiens (about 100,000 years ago), survives. In the early hominids, language was not used for communication, but for "modelling", that is, a refined analysis of their surroundings: the advantages of the forerunners of language were not primarily social, but the individual advantages for survival appear to have been critical. However, our species eventually readapted language into a series of linear manifestations, first speech and later other means, such as script, which flourish as systems supplementary to the more ancient and fundamental ones by which the modern human too communicates. Human verbal and various nonverbal means of communication are now so thoroughly intermingled that they can be disentangledonly by dint of careful scientific analysis.

As to ontogenesis, human infants are born with an array of nonverbal devices they can naturally use to communicate with adults in their immediate environment. They learn context many months before they learn linguistic devices, although the earlier forms (gaze,gesture, and so forth) don't get lost; they merely become contingent and optional. In senility and other circumstances of impairment, language is likewise attentuated and lost before the array of more ancient prelinguistic habits is dissolved.

Attention focused on communication studies, in the West, among the Greeks, in particular among those pioneering physicians who were concerned with describing interaction between themselves and their patients. Patients related verbally and displayed by nonverbal means their complaints (dubbed symptoms, which are kinds of indexical signs, that is, signs such as tracks, footprints, finger pointing, and, in language, pronouns) while reporting "I have a bellyache," or simply groaned while clutching their abdomen. The physicians asked searching questions about their patients' past ("took a case history") and examined them with hands ("palpation"), eyes, and ears, or with intruments measuring, for instance, such "vital signs" as blood pressure, temperature, and so forth. Summating their partient's symptoms, or subjective signs, with their own objective detection of other signs, they pronounced a diagnosis of the syndrome, and, evaluating that in the light of their overall experience, they made a prognosis. These notions and terms were known to Hippocrates and actually spelled out in a treatise by his follower, the prolific Galen.

Both Plato and Aristotle were concerned with problems of everyday communication and its specialized uses, for example, in poetics or the rhetoric of persuasion. For several Hellenistic schools of philosophy, notably the Stoics and the Epicureans, theories of language and of the sign, and of communication, were central preoccupations. The great Ancient rhetoricians, including Cicero and Quintilian, concentrated on the techniques of expression, a field which today focuses on the study of misunderstanding and ways to remedy it. The most outstanding thinker of antiquity on issues such as these was Saint Augustine, who also proposed the first coherent concept of the lie.

During the Middle Ages, studies of logic and language flourished and led to elaborate considerations of a philosophy of grammar and of principles of a "universal grammar." Locke's work of 1690 became enormously influential in examinations of the meaning of "meaning," and he can indeed be considered a forerunner of modern semiotics. Debates concerning universals and other aspects of communication were significantly advanced by Leibniz.

The nineteenth century, and the first decades of the twentieth, were marked by an explosive development of most of the basic communication technologies still in use: photography and telegraphy, the rotary press, the typewriter, the transoceanic cable, the telephone, motion pictures, wireless telegraphy, magnetic tape recording, radio, and television. These rapid changes in mass media and telecommunications (most recently, satellite) technologies, such as interactive TV as well as elecontronic mail and funds transfer, facsimile machines, and computer bulletin boards, are sometimes (for example, Beniger1986) referred to as components of the "control revolution." Because the concept of communication is so central to our contemporary civilization, and because of the intensive social shaping of technology by governments and commercial interests, our age has increasingly come to be characterized as "the information society".

Communication studies have hitherto dealt predominantly with the past and the present, but speculative extrapolations toward the future have also been made. It is clear that such studies are inevitably linked to the biological fate of humankind. In 1980 the U.S. department of Energy created a task force to investigate problems connected with the final marking of a filled nuclear-waste repository - to devise a method of warning future generations, up to 10,000 years hence, not to mine or drill at that site unless they are fully aware of the consequences of their actions. A significant component of this investigation was devoted to the question of how our generation can communicate with up to three hundred generations into the future. The report - which has become particularly relevant in view of the preliminary selection by the U.S. Congress, in 1987, of a site in Nevade - recommended, among other items, that a relay system of recoding messages be launched and that messages to be actually displayed be imbued with the maximum possible redundancy.

In any event, in the future, communication will increasingly depend on developments in biotechnology and computer technology, which already provide humanity with opportunity to redesign itself.