Units of paper quantity Simon Winchester, in "The Surgeon of Crowthorne", cites a specific number, defining quire as "a booklet eight pages thick." Several European words for quire keep the meaning of "book of paper": Ger. "Buch von Papier", Dan. "bog papir", Du. "bock papier". In blankbook binding, "quire" is a term indicating 80 pages. A ream of paper is a quantity of sheets of the same size and quality. International standards organizations define the ream as 500 identical sheets. This ream of 500 sheets (20 quires of 25 sheets) is also known as a 'long' ream, and is gradually replacing the old value
Paper × 841 mm). A1 is half the size of a sheet of A0 (i.e., 594 mm × 841 mm), such that two sheets of A1 placed side by side are equal to one sheet of A0. A2 is half the size of a sheet of A1, and so forth. Common sizes used in the office and the home are A4 and A3 (A3 is the size of two A4 sheets). The density of paper ranges from for tissue paper to for some speciality paper. Printing paper is about . Paper may be classified into seven categories: Some paper types include: