As the form (mass) rotates clockwise, its contents (particles) rotate counter-clockwise.[br]You can check "Content Marker" and "Waveform" to see them clearly.[br]Actually, each content particle oscillates between counter-clockwise and clockwise directions:[br][list][*]When the contents are far from the form, they're [i][b]free[/b][/i] (dispersed, scattered, diverged), and move in the opposite direction with the form, i.e. counter-clockwise.[/*][*]When the contents are near to the form, they're [b][i]conforming[/i][/b] (gathered, concentrated, converged), and move following the form, i.e. clockwise.[/*][/list]This is the nature of wave. Here the form is the waveform and of that wave.[br]This phenomenon can also be seen clearly in the [url=https://www.geogebra.org/m/sfusfsmq]water wave[/url] (in the applet, check "Particles" and watch the green water wave).