Munroe, author of the popular webcomic, published a book last November called Thing Explainer: Complicated Stuff in Simple Words, which explains the laws of science using only the English language's 1,000 most common words. Brains became "thinking bags," and the Saturn V rocket became the "U.S. Space Team Up Goer," with diagrams and his trademark stick figures all around.
Thing Explainer also happens to be published by Houghton Mifflin Harcourt, a major textbook publisher. Some page proofs of the book found their way beneath the eyes of the textbook division's editors, and things seemed to click naturally from there.
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