Rods are basically made from carbon.
Plastic, composite carbon combined with Kevlar, which is a kind of material that is bullet proof, or just high carbon.
Since the carbon's force and strength in connection to its mass is light, making it strong material that can allow thinner fabrication but still is able to keep the span and length.
A rod that is lighter evidently handling will be easier, controlling it would be less tiring on ones arms and reduces resistance to air giving one an easier time accurately casting it, particularly on windy ways.
