What is the Difference between Displacement Node Normal Node and displace modifier? The Displacement node doesn't seem to be much different than a normal map, where as the displacement modifier will actually effect the geometry.  Am I missing something here, is there a difference in the node tree between normal mapping and displacement?
Displacement modifier: affect geometry directly

Normal map: affects polygons perceived orientation in regard to how they reacts to light

Displacement node: affect geometry when rendered (need to be rendering with cycles and turn on displacement in material settings)