Communication lies at the heart of social interaction. Everyday life is full of communication, of one sort or another. We communicate with other people, or receive communications from them, all the time, by talking to one another and through written language. We also signal to one another, using a whole range of cues, and we respond to the more general forms of communication used by society, which apply to everyone, and don’t just originate from any single person. As we saw in the last chapter, communication can take many forms. But what is really important is how people actually use communication — the function it serves, as opposed to its form.