For the curious, the ISO standard is ISO/IEC 14977. It is available here: https://standards.iso.org/ittf/PubliclyAvailableStandards/ https://standards.iso.org/i

For the curious, the ISO standard is ISO/IEC 14977. It is available here: https://standards.iso.org/ittf/PubliclyAvailableStandards/ https://standards.iso.org/ittf/PubliclyAvailableStandards/ Direct link to the standard: https://standards.iso.org/ittf/PubliclyAvailableStandards/s026153_ISO_IEC_14977_1996(E).zip https://standards.iso.org/ittf/PubliclyAvailableStandards/s0... But of course, as shanka commented, it isn't a standard that is followed practically. This is just a demonstration of https://xkcd.com/927/ https://xkcd.com/927/ in real life.