How did the imagination of science fiction writers become the reality of today? (Part 3)

Cell phone in 1948: Space Cadet
Robert A. Heinlein, who is described as one of the “three great masters of science fiction” together with Arthur C. Clarke and Isaac Asimov, in his novel Space Cadet, talks about one of the most important technological devices that cause today’s big technology companies to compete with each other, cell phones. In the novel, he states that a person traveling from Iowa to Colorado receives a call from his father for a phone he carries in his pocket. The protagonist of the novel…