Mark Twain. Mark Twain, formerly known as Samuel Langhorne Clemens, is an American writer and speaker. "Mark Twain" is his pen name, which was originally a term used by sailors of Mississippi River to indicate the water depth measured on the waterway. Man is moved because he lives in love. This is a famous saying of Mark Twain. /kloc-when he was 0/2 years old, his father died and he had to drop out of school to work as a coolie in the factory. Worked as a pilot, miner and journalist on the Mississippi River. I gradually began to write some interesting novels and started my writing career. His representative works include the novel One Million Pounds, The Adventures of Huckleberry Finn, The Adventures of Tom Sawyer, etc.