Download the Book (PDF): Introduction A trained musician who hears thirty seconds of an unfamiliar recording can usually say a surprising amount about it. Roughly how fast it goes and where the downbeats fall. Whether it is in a major or minor key, and when it modulates. Which instruments are playing, and which of them carries the tune. Whether the singer is pushing against the beat or sitting behind it. Whether this is the verse or the chorus, and how many times the chorus i

Download the Book (PDF): Introduction On a public blockchain, a trade is announced before it happens. When someone asks a decentralized exchange to swap one token for another, the request does not travel privately to a matching engine. It is broadcast to a network of computers, sits in a shared waiting area, and is visible to anyone running software that watches that waiting area. For a few seconds, sometimes less, the world knows what the trader intends to do, roughly how mu

Download the Book (PDF): Introduction On March 29, 1960, the New York Times ran a full-page advertisement under the headline "Heed Their Rising Voices." It had been paid for by a committee supporting Martin Luther King Jr., and it described, in general terms, a wave of repression against civil rights protesters in the South. Some of its details were wrong. The police had not "ringed" the Alabama State College campus in Montgomery; the students had sung a different song from t

Download the Book (PDF): Introduction Type the name of a famous scientist into a search engine and, alongside the list of links, a panel appears. It gives a birth date, a death date, a photograph, a spouse, the institutions where the person worked, the prizes they won, and a short row of "people also search for" names. None of this is a document. Nobody wrote that panel as a page. It is assembled on the fly from a store of facts about a thing the search engine has decided exi

Download the Book (PDF): Introduction A forty-tonne articulated truck leaving a distribution centre in the Rhine valley at five in the morning will, on a typical long-haul day, cover somewhere between 600 and 900 kilometres. A diesel version of that truck burns roughly a third of a litre of fuel for every kilometre and refuels in a few minutes at any of thousands of stations. Its engine is designed to run for well over a million kilometres. Nothing about this arrangement is g

Download the Book (PDF): Introduction Every autumn, somewhere around the second or third week of October, a certain kind of student begins to lose the thread. Nothing dramatic happens. The alarm goes off and the room is still dark, so the snooze button gets pressed twice instead of once. The eight o'clock lecture becomes a recording to watch later. Lunch turns into an afternoon of cereal and bread. A friend texts about a movie night and the reply is "maybe next time," typed f