The essential properties of the potential function associated to classical links by \textit{J. H. Conway} [Comput. Probl. abstract Algebra, Proc. Conf. Oxford 1967, 329-358 (1970; Zbl 0202.547)], in both its unreduced (multivariate) and reduced forms, are presented. (This potential function is a version of the classical Alexander polynomial, normalized so as to be an absolute invariant of link type.) The author makes the interesting observation that though the reduced form \(\Omega\) (t) of the potential function is completely characterized by Conway's identity \(\Omega_+(t)=\Omega_-(t)+(t-t^{-1}) \Omega_ 0(t)\) and the fact that the unknot has \(\Omega =1,\) it is not known whether the unreduced form can be characterized in any analogous way. Unfortunately, the author's orientation convention is the opposite of Conway's, so that (for instance) the link here called the ''positive'' Hopf link (with potential function \(\nabla =1)\) would have \(\nabla =-1\) according to Conway.