ISO 4217 instead of translated currency names or ambiguous currency symbols. ISO 4217 codes are used on airline tickets and international train tickets to remove any ambiguity about the price. The first two letters of the code are the two letters of the ISO 3166-1 alpha-2 country codes (which are also used as the basis for national top-level domains on the Internet) and the third is usually the initial of the currency itself. So Japan's currency code is JPY—JP for Japan and Y for yen. This eliminates the problem caused by the names "dollar, franc, peso" and "pound" being used in dozens
ISO 31 ISO 31 ISO 31 (Quantities and units, International Organization for Standardization, 1992) is a deprecated international standard for the use of physical quantities and units of measurement, and formulas involving them, in scientific and educational documents. It is superseded by ISO/IEC 80000. The standard comes in 14 parts: A second international standard on quantities and units was IEC 60027 . The ISO 31 and IEC 60027 Standards were revised by the two standardization organizations in collaboration (, ) to integrate both standards into a joint standard "ISO/IEC 80000 - Quantities and Units" in which the quantities and equations used with