A fuel cell consists of two electrodes, the anode and the cathode, and an electrolyte. The operating principle is know from electrolysis, where it proceeds in an inverse fashion – water is split into hydrogen and oxygen while consuming power. In the fuel cell the fuel is oxidized at the anode, which releases electrons which move to the cathode through the electrical circuit and react with oxygen. The movement of electrons through the circuit allows a current to be drawn, as long and fuel and oxygen is supplied to the cell. The animation schematically illustrates the operating principle.