(2001)
Young hobbit Frodo Baggins, after inheriting a mysterious ring from his uncle Bilbo, must leave his home in order to keep it from falling into the hands of its evil creator. Along the way, a fellowship is formed to protect the ringbearer and make sure that the ring arrives at its final destination: Mt. Doom, the only place where it can be destroyed.
See how this movie compares to the book it was based on

by John Ronald Reuel Tolkien
An epic depicting the Great War of the Ring, a struggle between good and evil in Middle-Earth, in which the tiny Hobbits play a key role.
Tom Bombadil completely omitted from the films
Most voted differences across all source material
The entire Tom Bombadil sequence from the Old Forest is removed from the film adaptation.