Kinesics is the interpretation of body motion communication such as
facial expressions and
gestures — that is, nonverbal behavior related to movement of any part of the body or the body as a whole. The equivalent popular culture term is
body language, a term
Ray Birdwhistell—considered the founder of this area of study—never used, and did not consider appropriate (on the grounds that what can be conveyed with the body does not meet the linguist's definition of language). Even so, many people use this term.