what power does it grants ?
Control of the other Rings of Power and domination of the wills of their users, a mortal wearing the Ring became effectively invisible except to those able to perceive the non-physical world
One Ring
The Ring's primary power was control of the other Rings of Power and domination of the wills of their users. The Ring also conferred power to dominate the wills of other beings whether they were wearing Rings or not—but only in proportion to the user's native capacity. In the same way, it amplified any inherent power its owner possessed.

A mortal wearing the Ring became effectively invisible except to those able to perceive the non-physical world, with only a thin, shaky shadow discernible in the brightest sunlight
who forged the ring in lord of the rings The Dark Lord Sauron what is the genre of it? UNANSWERABLE who created it? According to J. R. R. Tolkien's "The Lord of the Rings", the One Ring was forged by the Dark Lord Sauron
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One Ring [SEP] Powers
Except for Tom Bombadil, nobody seemed to be immune to the corrupting effects of the One Ring, even powerful beings like Gandalf and Galadriel, who refused to wield it out of the knowledge that they would become like Sauron himself. Within the land of Mordor where it was forged, the Ring's power increased so significantly that even without wearing it the bearer could draw upon it, and could acquire an aura of terrible power. When Sam encountered an Orc in the Tower of Cirith Ungol while holding the Ring, he appeared to the terrified Orc as a powerful warrior cloaked in shadow "[holding] some nameless menace of power and doom".