Gandalf is known as the Grey Pilgrim in J.R.R. Tolkien’s The Lord of the Rings.
The title reflects Gandalf’s wandering life, his grey robes, and his role as a guide who travels widely through Middle-earth. He is one of the Maiar, immortal spiritual beings who entered Middle-earth in embodied form as the Istari, or Wizards. In The Lord of the Rings, he is also called Gandalf the Grey.
After confronting the Balrog in Moria, Gandalf returns as Gandalf the White. That transformation marks a change in authority and appearance, but it is still the same character. Saruman is another Istar who becomes Saruman the White, while Radagast is associated with brown. These similar color titles can make the Wizards easy to mix up.