Many paper size standards conventions have existed at different times and in different countries. Today, there is one widespread international ISO standard (including A4, B3, C4, etc.) and a local standard used in North America (including letter, legal, ledger, etc.). The paper sizes affect writing paper, stationery, cards, and some printed documents. The standards also have related sizes for envelopes.
== Grain ==
Most industry standards express the direction of the grain last when giving dimensions (that is, 17×11 inches is short grain paper and 11×17 inches is long grain paper), althou...