Although the scientific study of gesture is still in its infancy, some broad categories of gestures have been identified by researchers. The most familiar are the so-called emblems or quotable gestures. These are conventional, culture-specific gestures that can be used as replacement for words, such as the handwave used in the US for "hello" and "goodbye". A single emblematic gesture can have a very different significance in different cultural contexts, ranging from complimentary to highly offensive.[11] The page List of gestures discusses emblematic gestures made with one hand, two hands, hand and other body parts, and body and facial gestures.