Yesterday, I read about TEM waves on wikipedia. Those are waves that have no electric or magnetic field vectors pointing into propagation direction of the wave.
But on any picture illustrating EM waves, they are showing TEM waves instead of the (normal?) non-TEM waves. Before reading about TEM waves, I thought that there exist only TEM waves (i.e that the characteristic about EM waves is that they are transversal).
When do non-TEM waves get created and what factors do influence the angle of oscillation of the electric and/or magnetic fields of an EM wave? How do these waves behave different in practice?
Thanks for any insight!