The history of communication dates back to prehistory, with significant changes in communication technologies (media and appropriate inscription tools) evolving in tandem with shifts in political and economic systems, and by extension, systems of power. Communication can range from very subtle processes of exchange, to full conversations and mass communication. Human communication was revolutionized with speech approximately 100,000 years ago. Symbols were developed about 30,000 years ago, and writing in the past few centuries.
Petro glyphs The next step in the history of communications is petroglyphs, carvings into a rock surface. It took about 20,000 years for homo sapiens to move from the first cave paintings to the first petroglyphs, which are dated to around 10,000BC. It is possible that the humans of that time used some other forms of communication, often for mnemonic purposes – specially arranged stones, symbols carved in wood or earth, quipu-like ropes, tattoos, but little other than the most durable carved stones has survived to modern times and we can only speculate about their existence based on our observation of still existing ‘hunter-gatherer’ cultures such as those of Africa or Oceania.
Pictograms A pictogram (pictograph) is a symbol representing a concept, object, activity, place or event by illustration. Pictography is a form of proto-writing whereby ideas are transmitted through drawing. Pictographs were the next step in the evolution of communication: the most important difference between petroglyphs and pictograms is that petroglyphs are simply showing an event, but pictograms are telling a story about the event, thus they can for example be ordered in chronological order. Pictograms were used by various ancient cultures all over the world since around 9000 BC, when tokens marked with simple pictures began to be used to label basic farm produce, and become increasingly popular around 6000-5000 BC. They were the basis of cuneiform and hieroglyphs, and began to develop into logographic writing systems around 5000 BC.
Ideograms Pictograms, in turn, evolved into ideograms, graphical symbols that represent an idea. Their ancestors, the pictograms, could represent only something resembling their form: therefore a pictogram of a circle could represent a sun, but not concepts like ‘heat’, ‘light’, ‘day’ or ‘Great God of the Sun’. Ideograms, on the other hand, could convey more abstract concepts, so that for example an ideogram of two sticks can mean not only ‘legs’ but also a verb ‘to walk’.
Because some ideas are universal, many different cultures developed similar ideograms. For example an eye with a tear means ‘sadness’ in Native Americanideograms in California, as it does for the Aztecs, the early Chinese and the Egyptians. Ideograms were precursors of logographic writing systems such as Egyptian hieroglyphs and Chinese characters. Examples of ideographical proto-writing systems, thought not to contain language-specific information, include the Vinca script (see also Tărtăria tablets) and the early Indus script. In both cases there are claims of decipherment of linguistic content, without wide acceptance.