Most of the basic communication gestures are the same all over the world. When people are happy they smile; when they are sad or angry they frown or scowl. Nodding the head is almost universally used to indicate ‘yes’ or affirmation. It appears to be a form of head lowering and is probably an inborn gesture, as it is also used by deaf and blind people. Shaking the head from side to side to indicate ‘no’ or negation is also universal and may well be a gesture that is learned in infancy.