There are many movements used in sign language, including arcs, straight lines and ``wavy'' patterns. They are not necessarily two-dimensional (consider the sign for crazy, which in Auslan is the universal gesture of pointing to the head and making small circles directed away from the head), and can include changes in orientation and handshape as well as position. Typically, they can include multiple steps, such as the sign for science which is characterised by ``mixing test-tubes''.