Galvanic cells harness the electrical energy available from the electron transfer in a redox reaction to perform useful electrical work. The key to gathering the electron flow is to separate the oxidation and reduction half-reactions, connecting them by a wire, so that the electrons must flow through that wire. The anode is the electrode where oxidation, loss of electrons, takes place in a galvanic cell, it is the negative electrode, as when oxidation occurs, electrons are left behind on the electrode. These electrons then migrate to the cathode, positive electrode.