Hot Type is the epic story of the magnificent 19th-century machine that rendered Gutenberg’s movable type obsolete and opened the portal to the long century of mass media. The Linotype mechanized the 400-year-old process of setting type one laborious letter at a time, and thus ignited an explosion of newspaper, book, and magazine empires. This is a tale populated with wondrous characters: tragic inventors, malign media moguls, hand-typesetters called the Swifts who turned their craft into a spectator sport, and authors and journalists who chronicled the turmoil of their time, their every word molded into metal type by what some viewed as a thinking machine. This revolution in media technology helped to propel Mark Twain into literary celebrity, but it also cost him his fortune – as well as his sense of humor and optimism. The era of the Linotype was a bridge between Twain’s Gilded Age with its tycoons of steam, steel, and wire and today’s Gilded Age with its barons of bits and AI. Its history provides an opportunity to reflect on how technology changes culture just as new technologies – the internet and artificial intelligence –manufacture their endless streams of words today.