For 3D coordinate systems, right hand rule
requires the z axis
to be oriented in the direction your thumb points in after orientating your
hand along the x axis
and curling your fingers towards the y axis.
right hand rule is used to define orientation (winding) of planar objects.
rotations, if you put your right thumb along the axis of rotation, your fingers
will curl around in the direction of a positive (anti-clockwise) rotation.