Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910), known by the pen name Mark Twain, was an American writer, humorist, and essayist. He was praised as the "greatest humorist the United States has produced," with William Faulkner calling him "the father of American literature." Twain's novels include The Adventures of Tom Sawyer (1876) and its sequel, Adventures of Huckleberry Finn (1884), with the latter often called the "Great American Novel." He also wrote A Connecticut Yankee in King Arthur's Court (1889) and Pudd'nhead Wilson (1894), and co-wrote The Gilded Age: A Tale of Today (1873) with Charles Dudley Warner.

Twain was raised in Hannibal, Missouri, which later provided the setting for both Tom Sawyer and Huckleberry Finn. He served an apprenticeship with a printer early in his career, and then worked as a typesetter, contributing articles to his older brother Orion Clemens' newspaper. Twain then became a riverboat pilot on the Mississippi River, which provided him the material for Life on the Mississippi (1883). Soon after, Twain headed west to join Orion in Nevada. He referred humorously to his lack of success at mining, turning to journalism for the Virginia City Territorial Enterprise.

Twain first achieved success as a writer with the humorous story "The Celebrated Jumping Frog of Calaveras County," which was published in 1865; it was based on a story that he heard at Angels Hotel in Angels Camp, California, where Twain had spent some time while he was working as a miner. The short story brought Twain international attention. He wrote both fiction and non-fiction.