Gandalf is the wizard who guides Bilbo Baggins and the Fellowship in J.R.R. Tolkien’s stories.
In The Hobbit, Gandalf helps organize the expedition to the Lonely Mountain and recognizes that Bilbo can serve as the company’s burglar. In The Lord of the Rings, he becomes central to the effort to identify and destroy the One Ring.
Gandalf is one of the Istari, emissaries sent to Middle-earth to oppose Sauron. His original form is Gandalf the Grey. After confronting the Balrog in Moria, he returns as Gandalf the White, with greater authority and a changed appearance.
Saruman is another wizard and initially the head of the order, while Radagast is associated with animals and the wild. Their separate identities are a common source of confusion in adaptations and popular summaries.