Willingly or not, humans, when in co-presence, continuously inform one another about their intentions, interests, feelings and ideas by means of visible bodily action. For example, it is through the orientation of the body and, especially, through the orientation of the eyes, that information is provided about the direction and nature of a person's attention. How people arrange their bodies and how they orient them and place them in relation to each other or to features in the environment, provides important information about how they are engaged with one another and about the nature of their intentions and attitudes. Activities in which objects in the environment are being manipulated, modified or rearranged, are indispensable for grasping a person's aims and goals and interests. Of equal importance, however, are actions that are seen to be purely expressive. Here we find those configurations of action in the face and body that appear as displays of feeling and emotion, as well as actions that often play a central role in the accomplishment of important moments in social interaction. Greeting, showing gratitude or affection, challenge, threat, submission, compliance, all are accomplished through a range of different expressive actions.

Beyond this, however, are those actions that are employed as a part of the process of discourse, as a part of uttering something to another in an explicit manner.