Units of paper quantity and US measure, in some sources, a quire was originally 24 sheets.) Quires of 15, 18 or 20 sheets have also been used, depending on the type of paper. The current word "quire" derives from OE "quair" or "guaer", from OF "quayer", "cayer", (cf. modern Fr. "cahier"), from L. "quaternum", "by fours", "fourfold". Later, when bookmaking switched to using paper and it became possible to easily stitch 5 to 7 sheets at a time, the association of "quaire" with "four" was quickly lost. In the Middle Ages, a quire (also called a "gathering") was most often formed of 4 folded
Ruled paper lighter lines 2 mm (appx. 5/64 in) apart between each pair of heavy lines. Heavy vertical lines are spaced 8 mm (appx. 5/16 in) apart, beginning 16 mm (appx. 5/8 in) from the left-hand edge of the page. These sheets of paper are generally known as "grands carreaux" (large tiles) as opposed to the "petits carreaux" (small tiles) which are 5x5mm. Seyès ruled paper is available in single sheets ("copies simples") or joined double sheets ("copies doubles") which are sometimes preferred for exams, being easier to handle. DIN 16552:1977-04 (“Lines for handwriting”) specifies the types of ruled paper to be