Now, resistance itself depends on three important factors. So recall that the resistance of an electric current moving inside a wire depends on the cross sectional area of that wire, its thickness. It depends on the length of that wire, and it also depends on an internal property known as the resistivity, which basically depends on the type of material that that wire is made of. So this equation basically summarizes what we just said. So this equation describes the relationship between the resistance as well as the length, the area and our resistivity. So the resistance of the wire is equal to the product of our resistivity row multiplied by L, the length divided by a it's cross sectional area.