Language includes non-verbal as well as verbal symbolic communications. There is Sign language and Body Language. All communication with others is symbolic and involves the use of language, sound, bodily gesture and expression.
Symbolic communications are demonstrated by the cars we drive, the houses we live in, and the clothes we wear (e.g. uniforms – police, military). The most important aspects of symbolic communication are the words we use.
"Sociality is both necessary and sufficient for symbolic communications to 'get off the ground'."
Terrence W. Deacon combines human evolutionary biology and neuroscience together in researches and hopes to shed light to evolution of human cognition. Deacon believes the complex symbolic communications ability possessed by human, is the driving force for language evolution. According to Deacon, human more or less “discover” language during the exploration of the complex relationship between symbols and what they refer to in the real world.
The oldest surviving symbolic communications of humans are graffiti that were scratched or painted on protected rock surfaces. Some regard this material as art, which is clearly a matter of taste. As time went on, more elaborate iconography developed and was used both to communicate ideas and to provide decorations on pottery and other manufactured items and eventually on large scale stone carvings, but zenith of iconography was not reached until after the invention of the spray paint can.
The earliest traces of Homo sapiens are marked with cave paintings, reminding us of the depth of the human investment in visual expression and the range and power of symbolic communications.
Symbolic communications are the things that we have given meaning to and that represent a certain idea we have in place, for example, the American flag is a symbols that represent freedom for the Americans themselves, or imperialism and evil for some other countries.