One of the most important inventions in the shape of books was developed by the Romans. The earliest books were written on rolls - a long, continuous scroll of papyrus sheets attached together. The text of the book was written in columns and the reader rolled the scroll to get to each new page. These rolls were stored on shelves or in boxes or baskets.
Around the 1st century AD, the Romans made books similar to the ones we read today. They used rectangular sheets of parchment or papyrus folded in the center and sewn together. This form of book was called a codex. They were easier to read because you could move quickly to different parts of the book rather than rolling through an entire scroll to get to a section at the end.