Gandalf is a powerful wizard found in J. R. R. Tolkien's Middle-earth legendarium, appearing prominently in The Hobbit and The Lord of the Rings. The elves call him Mithrandir, as do the men of Gondor. Gandalf is not a popular guest in many places, simply because he tells the truth and demands action. those who prefer to hide or watch the war go by hate him.
Mithrandir means the Grey Pilgrim. It is revealed by Faramir to Frodo that one of Gandalf's Names is Olorin, disclosing the fact that Gandalf is a Maiar of great power who came from the West.