J.R.R. Tolkien called the powerful ring sought by Sauron the One Ring. Sauron forged it in the fires of Mount Doom to control the other Rings of Power.
The One Ring contains much of Sauron’s power, which makes it both a weapon and a dangerous extension of its maker. Its inscription is written in the Black Speech of Mordor and appears when the Ring is heated.
The Ring can make its wearer invisible to ordinary sight, but it also draws attention from Sauron and corrupts those who possess it. Its destruction requires returning it to Mount Doom, the place where it was forged. The title is distinct from the three Elven Rings, the seven Dwarf-rings, and the nine rings of Men.