Adventures of Huckleberry Finn is a novel by Mark Twain. It is told in the first person by Huckleberry "Huck" Finn, a friend of Tom Sawyer and narrator of two other Twain novels. The book is noted for its colorful description of people and places along the Mississippi River. Set in a Southern antebellum society that had ceased to exist about 20 years before the work was published, Adventures of Huckleberry Finn is an often scathing satire on entrenched attitudes, particularly racism. Perennially popular with readers, Adventures of Huckleberry Finn has also been the continued object of study by literary critics since its publication. It was criticized upon release because of its coarse language and became even more controversial in the 20th century because of its perceived use of racial stereotypes and because of its frequent use of the racial slur "nigger", despite arguments that the protagonist and the tenor of the book are anti-racist.