The title used for those three Hobbits (Bilbo Baggins, Frodo Baggins and Samwise Gamgee) who had at one time borne the One Ring, and aided in its destruction. Because of their status as Ring-bearers, they were granted the passage of the Straight Road, and each eventually went to the Blessed Realm to live out their lives.
Though only these three Hobbits are strictly counted as Ring-bearers, in fact the Ring was borne by other hands besides. Those who actually wore the Ring, as opposed to picking it up or holding it, are shown in bold.
Sauron He forged the One Ring for himself in c.1600 (Second Age) and bore it for c.1,840 years until his defeat in the Siege of Barad-dûr in 3441 (Second Age). Isildur Against the advice of Elrond and Círdan, he took the Ring for himself. He did not bear it long - two years later, Isildur was ambushed by Orcs and the One Ring was lost in the Anduin, where it lay hidden for most of the Third Age. Déagol He discovered the Ring while fishing the Gladden Fields in about the year III 2463. He held it for only a short time before he was murdered by his friend Sméagol (Gollum), who stole the Ring for himself. Gollum He took the Ring from Déagol, and soon hid with it in the roots of the Misty Mountains. He bore it in the dark for almost five hundred years. Bilbo Baggins He discovered the Ring 'by accident' while imprisoned beneath the Misty Mountains in July 2941, and claimed it from Gollum by defeating him in a Riddle-game. He carried it eastward to Erebor, and then back westward to the Shire, where he kept it. He bore the Ring for almost exactly sixty years. Frodo Baggins He was given the Ring by Bilbo on the advice of Gandalf. He was the Ring-bearer, who carried the One Ring from the Shire to Orodruin, to the very brink of the Cracks of Doom. Once there, the Ring's power overmastered him, and he named it to himself, but Gollum bit it from his finger and fell into the Fire. Frodo bore the Ring for seventeen years until its destruction. Gandalf He held it for a matter of moments on the morning of 13 April III 3018, before throwing it into Frodo's fire. This was the moment that the Ring's fiery inscription appeared, confirming that it was the One Ring. Tom Bombadil He wore it on his finger for a moment on 27 September III 3018, but was famously unaffected by it. The reason that Tom was immune was the effects of the Ring remains an abiding mystery. Samwise Gamgee He bore the Ring for about two days in March 3019 (Third Age), while Frodo his master was in the clutches of Orcs in the Tower of Cirith Ungol.