In late April 1963, in the D Ring of the massive new building called the Pentagon, J.C.R. Licklider sat before a typewriter in his office, working on a memo. A member of the Defense Department’s Advanced Research Projects Agency (ARPA)—he wore the thick-rimmed black glasses popular among engineers of the era to prove it—Licklider addressed his memo to “Members and Affiliates of the Intergalactic Computer Network,
