Gandalf is the wizard who helps Bilbo begin his adventure in J.R.R. Tolkien’s The Hobbit. He brings the dwarves to Bag End and identifies Bilbo as the burglar needed for Thorin Oakenshield’s expedition to the Lonely Mountain.
Gandalf is one of the Maiar, powerful spiritual beings who came to Middle-earth in the form of an elderly wizard. In The Hobbit, he acts as an adviser, protector, and catalyst for the story. He leaves and rejoins the company at several points, including the confrontation with the Necromancer at Dol Guldur.
In The Lord of the Rings, Gandalf becomes central to the struggle against Sauron. His transformation from Gandalf the Grey into Gandalf the White follows his battle with the Balrog on the Bridge of Khazad-dûm. A common error is treating Gandalf, Saruman, and Radagast as different species; all three are members of the Istari order sent to Middle-earth.