What is Immunity, corrosion and passivation domains?

On the diagram of a metal, the domain of the metal itself is its immunity domain (it cannot be oxidised); the domains of its dissolved ions form the corrosion domain; the domains of its solid oxides and hydroxides, which may coat the metal, form the passivation domain. Whether a coat really protects the metal is a kinetic matter, treated in the Year 2 volume.