One rainy afternoon, Mara stumbled across a scribbled note in a secondhand book: “Adobe Photoshop CC 2013 — 64 Bit — Free.” The handwriting looked urgent, like someone who’d written it in a rush and folded the paper into quarters. She laughed at the absurdity. “Free,” she said aloud, “and from 2013? That’s ancient.” But curiosity tugged at her—partly for the program itself and partly for the story behind the scrap of paper.