Gandalf is the wizard who guides Bilbo Baggins in The Hobbit.
He arranges Bilbo’s participation in Thorin Oakenshield’s expedition to reclaim the Lonely Mountain from the dragon Smaug. Gandalf recognizes that Bilbo’s qualities, including courage and resourcefulness, may make him a valuable burglar despite his reluctance.
In Tolkien’s wider mythology, Gandalf is one of the Istari, spiritual beings sent to Middle-earth to oppose Sauron. His original name is Olórin, and he later returns as Gandalf the White after confronting the Balrog in Moria. Saruman is another wizard, but he becomes an enemy rather than Bilbo’s guide.