Can anyone explain in simple terms what the term screening means? My intuition is that a metal is a good screener because in the presence of an external electric field its free electrons will rearrange themselves such that the electric field is zero inside the metal. But I am having a hard time coupling my intuition to something my teacher said the other day. He said that the screening properties are related to the permitivity of the material and that ε=∞ is a perfect screener. Can anyone help me draw the connection?