Units of paper quantity the 500-sheet ream has become the de facto international standard. A paper bundle is a quantity of sheets of paper, currently standardized as 1,000 sheets. A bundle consists of 2 reams or 40 quires. As an old UK and US measure, it was previously equal to 960 sheets. When referring to chipboard, there are two standards in the US. In general, a package of approximately 50 pounds of chipboard is called a bundle. Thus, a bundle of 22 point chipboard (0.022" thick) 24" × 38", with each sheet weighing 0.556 pounds, contains 90 sheets. However, chipboard sold in size 11"
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: