ISO 4217 "ruble". In addition to codes for most active national currencies ISO 4217 provides codes for "supranational" currencies, procedural purposes, and several things which are "similar to" currencies: The use of an initial letter "X" for these purposes is facilitated by the ISO 3166 rule that no official country code beginning with X will ever be assigned. Because of this rule ISO 4217 can use X codes without risk of clashing with a future country code. ISO 3166 country codes beginning with "X" are used for private custom use (reserved), never for official codes. For instance, the ISO 3166-based NATO country
International Organization for Standardization Central Secretariat based in Geneva. A Council with a rotating membership of 20 member bodies provides guidance and governance, including setting the Central Secretariat's annual budget. The Technical Management Board is responsible for over 250 technical committees, who develop the ISO standards. ISO has formed two joint committees with the International Electrotechnical Commission (IEC) to develop standards and terminology in the areas of electrical and electronic related technologies. ISO/IEC Joint Technical Committee 1 (JTC 1) was created in 1987 to "[d]evelop, maintain, promote and facilitate IT standards", where IT refers to information technology. ISO/IEC Joint Technical Committee 2 (JTC 2)