In Catholic Faith and understanding:
The Holy Ghost is the Third Person of the Blessed Trinity.
Though really distinct, as a Person, from the Father and the Son, He is consubstantial with Them; being God like Them, He possesses with Them one and the same Divine Essence or Nature.
He proceeds, not by way of generation, but by way of spiration, from the Father and the Son together, as from a single principle.