HOUSTON—I'd guess that the majority of Ars readers are familiar with XKCD, the stick-figure Web comic drawn by former NASA contractor and engineer (and now Hugo award winner) Randall Munroe. It's rare for Ars to stop by a workplace to interview a source where there aren't XKCD comic strips festooning the walls (the "sudo make me a sandwich" comic is particularly popular among sysadmins), and discussion threads on forums across the Internet will frequently include a "relevant XKCD" link to emphasize or summarize a particular point with a comic on the topic.
Munroe draws and releases XKCD under Creative Commons licensing, and makes the majority of his income these days from XKCD merchandise—like his new book, Thing Explainer, which Munroe is currently promoting. The book takes the conceit demonstrated in the "Up-Goer Five" comic—labeling a diagram of a complex machine using only first thousand most-common English words—and goes nuts with it, breaking out dozens of different drawings with a similar labeling style. Highlights include "the pieces everything is made of" (the periodic table), the bags of stuff inside you (the organs and systems inside a human body), and "the shared space house" (the International Space Station).
Ars caught up with Munroe before a book-related talk at Space Center Houston, and he was kind enough to give us a few minutes to talk about space, Up-Goers, and the iterative process of explaining things.