The physical arrangement of the RBS book and print collection supports both classroom and independent study. The books are generally shelved by date (rather than by author or subject), to show the chronological development of parchment, leather, cloth, and paper bindings. Many of the prints are filed by technique (rather than by artist or engraver), to facilitate the identification of illustration processes. Other RBS collection arrangements assist the study of various formats, genres, materials, and physical features such as sewing structures, endpapers, and dust-jackets. An unusual feature of some of these collections is the presence of multiple copies (sometimes as many as a dozen or more) of the same (or almost the same) book—a duplication valuable not only for facilitating group viewing in the classroom but also for demonstrating the bibliographical principle that almost exactly the same can be another way of saying quite different.