“By the early centuries of the Christian era, bookshelves had to accommodate, in addition to scrolls, a growing number of bound manuscripts, or codices, which in time whould displace scrolls as the preferred format for books. The codex, named for the fact that it was covered with wood (codex means “tree trunk” in Latin), and which led to the term “code” in a legal context, was made by folding over flat sheets of papyrus or parchment and sewing them together into a binding.”

—Hentry Petroski, The Book on the Book Shelf, 1999.