Why Sauron wants the Ring?

[Belegorn]

Originally Posted by Drognan

Do we know what powers Ring provides? It's allready known that turns person invisible and greedy, it can control other rings, what else?

It enhances the innate powers of the bearer. But you basically got it all. It had the power to control the other Rings and the control the minds and know the thoughts of the wielders of the other Rings. All that is wrought or done with the other Rings he will know. Sauron could keep his power in the world and anything he built with it could not be destroyed. Elrond says, "His Ring was lost but not unmade. The Dark Tower was broken, but its foundations were not removed; for they were made with the power of the Ring, and while it remains they will endure." [FotR, p. 294] The Ring could not be destroyed by any craft less than Sauron's and we know when we are told of Sauron's forges that they were, "the greatest in Middle-Earth; all other power were here subdued." [RotK, p. 247]