As libraries move into the digital age, they're also expanding into territory long occupied by bookstores. The New York Times profiles libraries that have responded to customer demand for bestsellers, friendlier reading spaces, and other changes that make libraries less "intimidating." The need to cull physical books (especially transiently popular titles like Fifty Shades of Grey) to expand computer and reading space also means the expansion of library book sales. "A library has limited shelf space," says Arlington Heights library director Jason Kuhl, "so you almost have to think of it as a store, and stock it with the things that people want."