Isaac Asimov was science fiction's great popularizer, a biochemistry professor who wrote or edited over five hundred books across every genre and subject. This collection gathers stories that Asimov himself considered his best, including Nightfall, in which a civilization that has never known darkness confronts an eclipse, and The Last Question, which Asimov called his favorite among his own works. That story follows a computer through billions of years of cosmic evolution as humans repeatedly ask whether entropy can be reversed. Asimov's style is plain, his characters functional, his prose workmanlike. What elevates his fiction is conceptual reach and narrative ingenuity. He specialized in the puzzle story, in which a mystery is posed and solved through rational inference, and in the social extrapolation, imagining how technologies would transform societies over centuries. The Foundation series, his most ambitious work, drew on the idea that history might be predicted scientifically. These stories predate that ambition but share its concern with how intelligence, human and artificial, might shape the future. Asimov wrote during science fiction's golden age and helped define what the genre could accomplish. Readers coming to him now may find his style dated but his ideas surprisingly durable.