Lawyers use rather large notebooks known as legal pads that contain lined paper (often yellow) and are appropriate for use on tables and desks. These horizontal lines or "rules" are sometimes classified according to their space apart with "wide rule" the farthest, "college rule" closer, "legal rule" slightly closer and "narrow rule" closest, allowing more lines of text per page. When sewn into a pasteboard backing, these may be called composition books, or in smaller signatures may be called "blue books" or exam books and used for essay exams.