Isaac Asimov was one of the defining writers of twentieth-century science fiction, central to the development of golden age science fiction and best known for the Foundation stories, the Robot stories, and a vast body of fiction and nonfiction. His work helped establish many of the field's enduring concerns: rational inquiry, technological change, future history, robotics, alien intelligence, and the moral consequences of scientific discovery. Asimov's short fiction remains especially important to readers and collectors of classic science fiction, combining clear prose, ingenious premises, and speculative ideas designed to turn cleanly and memorably.