After approval of the DIS by the TC, the ISO Central Secretariat publishes the International Standard as ISO 999. Next to ISO there are other international organisations active in more limited areas, with standards of their own. There is ECMA, the European Computer Manufacturers Association, CEN, the European Standards Institution. Finally, IBM has its own Corporate Standards, which are often followed by other manufacturers. Against this background the development of what became eventually ISO 646 for 7-bit coding must be seen.
Many languages require more letters than English does.
All these had to find a proper place in the codetable to the cost of others. A solution was found by allowing options. This implied, however, leaving the principle that a byte is universally interpreted as always meaning the same character. Now the situation was created that a byte typed in as a parenthesis in one country could appear in another as a letter with umlaut. This incongruency was eliminated in 1991.