Units of paper quantity as ISO 4046. In Europe, the DIN 6730 standard for Paper and Board includes a definition of 1 ream of A4 80gsm (80 g/m) paper equals 500 sheets. The word 'ream' derives from Old French "reyme", from Spanish "resma", from Arabic "rizmah" "bundle" (of paper), from "rasama", "collect into a bundle". (The Moors brought manufacture of cotton paper to Spain.) Early variant rym (late 15c.) suggests a Dutch influence. (cf. Du. "riem"), probably during the time of Spanish Habsburg control of the Netherlands. The number of sheets in a ream has varied locally over the centuries, often according to the
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