Any great nonfiction book combines education with entertainment. In drafting my A-list of general-interest books about technology, I considered impact and significance but gave still more weight to the reading experience. This is a collection where lay readers can appreciate each entry—and engineers, programmers, and other tech professionals can't afford to miss a single one.

PHOTO: Timothy Archibald

The Pencil: A History of Design and Circumstance

Henry Petroski (Knopf, 1989)

Early in his exhaustive study of the invention, refinement, production, and commercial history of this humble and indispensable writing implement, Henry Petroski claims, “It is by trying to understand simple ideas and principles in terms of the most complex of examples and issues that we tend to feel overwhelmed.... What might seem to be the secrets of engineering are in the common as well as in the uncommon, in the small as in the large, in the seemingly simple as in the indubitably complex.” The Pencil justifies this contention. Though the lead-pointed device seemingly sprang out of nowhere (it is first mentioned in a 1565 book on fossils), Petroski traces its origins and skillfully follows its progress from early appearances to a product of the emerging age of assembly-line industries. He is less interested in the cultural history of the pencil than in its steady evolution. The cast of characters is not necessarily the most colorful bunch. A notable exception is Henry David Thoreau, whose name is associated not only with Walden Pond but also the leading 19th‑century pencil-making operation in America. The star here is really the stick of cedar and graphite we take for granted. Every aspect of the pencil—the graphite, the eraser, the shape, the color—is examined thoroughly. Maybe a little too much so, as Petroski can be long-winded and might have benefited from a more liberal application of an eraser. Nonetheless, The Pencil never loses sight of its point.

PHOTO: Timothy Archibald

Mirror Worlds; or, The Day Software Puts the Universe in a Shoebox…How It Will Happen and What It Will Mean

David Gelernter (Oxford University Press, 1991)

William Gibson, in Neuromancer, introduced the concept of “cyberspace as place.” And another sci‑fi writer, Neal Stephenson, in Snow Crash, took pains to explain how a computer-based world might work [see sidebar, “Favorite Fiction”]. But the prize for prescience goes to computer scientist David Gelernter, who in Mirror Worlds outlined how an alternative universe that reflected and interacted with physical reality would emerge. Though he knew that the picture he drew had elements of the cyberpunk to it, he bristled at the idea that his vision could be viewed as another version of Gibson's matrix or Stephenson's metaverse. “There is nothing science-fictionish about these programs,” Gelernter wrote. The book was written before the Internet exploded, and parts can seem dated. But time has proven it correct: our current connected state—always on, perpetually blogged, and geo‑tagged—is beginning to look a lot like one of these mirror worlds. Consider this thought: “When you switch on your city Mirror World, the whole city shows up on your screen, in a single dense, live, pulsing, swarming picture.” Sound familiar? While assessing the direction of open services like Google Maps and Facebook, I keep returning to Mirror Worlds as the best way to understand how computational reality coexists and merges with the physical world.