Gandalf is a character from a story called "The Lord of the Rings" written by J.R.R. Tolkien. Gandalf is a wizard who is tall and wise and has a long, white beard. He wears a long grey robe and a tall, pointed hat. Gandalf is a hero in the story who helps the other characters save their land from danger by giving them advice and helping them fight against an evil wizard. He also uses his magic to make things happen, like lighting a fire when the characters need it.