V.IV-. Folowing the Equator, a journey around the world. The Original Books Collection. Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910), better known by his pen name Mark Twain, was an American author and humorist. He is most noted for his novels, The Adventures of Tom Sawyer (1876), and its sequel, Adventures of Huckleberry Finn (1885), the latter often called "the Great American Novel."