Book excerpt: An illustrated journey through 250 milestones in computer science, from the ancient abacus to Boolean algebra, GPS, and social media. With 250 illustrated landmark inventions, publications, and events—encompassing everything from ancient record-keeping devices to the latest computing technologies—The Computer Book takes a chronological journey through the history and future of computer science. Two expert authors, with decades of experience working in computer research and innovation, explore topics including: the Sumerian abacus * the first spam message * Morse code * cryptography * early computers * Isaac Asimov’s laws of robotics * UNIX and early programming languages * movies * video games * mainframes * minis and micros * hacking * virtual reality * and more “What a delight! A fast trip through the computing landscape in the company of friendly tour guides who know the history.” —Harry Lewis, Gordon McKay Professor of Computer Science, Harvard University