Moby-Dick or The Whale is an 1851 novel by American writer Herman Melville. The book is the sailor Ishmael's narrative of the obsessive quest of Ahab, captain of the whaling ship Pequod, for revenge on Moby Dick, the giant white sperm whale that on the ship's previous voyage bit off Ahab's leg at the knee. A contribution to the literature of the American Renaissance, the work's genre classifications range from late Romantic to early Symbolist. Its reputation as a "Great American Novel" was established only in the 20th century, after the centennial of its author's birth.