Mark Twain, born Samuel Langhorne Clemens in 1835, was a famous American author, humorist, and social critic. He was friends with many influential figures of his time, including Helen Keller and presidents. Twain married his wife Olivia in 1870, with whom he had three daughters. Twain had a lifelong fascination with Halley's Comet since he was born shortly after its appearance, and he died just after it returned in 1910, fulfilling his prediction that he would come in and go out with the comet.