Hehe, more specifically, y is down to up, z from near to far.....

For the airplane world, simpler terms, pitch is rotation as imparted by the elevator, yaw by the rudder, and roll by the ailerons. Helis mess it up by having "pitch" be a major flight control (collective), and "aileron" and "elevator" contrived by the cyclic. We just dare to be different, I guess . At least the "rudder" (tail deflection, yaw) is something like what you expect!