Interaction with the purpose of sharing involves the exchange of the signs and symbols (i.e., words) In a given communicative context, the absence of them also still communicates the absence of the ‘ingredients’ of communication; the intention, the skills, or the presence of barriers.
Communication takes place when we are supposedly at the same level of understanding and comprehension as other interlocutors. Communication is therefore not what is said whether verbally or non-verbally, but what is understood. We have discussed earlier that understanding is influenced by perceptions and perceptions evolved over a period of time and color our understanding.
We all have personal perceptions, and therefore understanding would need a conscious and deliberate effort by us and cannot be left to chance, expecting it to happen by itself. Ask yourself how consciously you listen to others when they are speaking; or for that matter, how conscious you are, when speaking, about how many appear to be understanding.
Interestingly, communication, which is generally relegated to as basics when considered as an ordinary human faculty is not that basic after all. It is therefore that communication can be learnt and needs to be learnt.