by Markus Kuhn International Standard ISO 8601 specifies numeric representations of date and time.
There are so many formats available, most of them incompatible with others, that it can be a usability nightmare to choose a date representation when writing for an international, cross-cultural audience, as is the case on the web.
Fortunately, there is one solution in the ISO-developed international date format.
Especially authors of Web pages and software engineers who design user interfaces, file formats, and communication protocols should be familiar with ISO 8601.
Contents: Date, time of day, time zone, software hints.
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The date of a particular event depends on the observed time zone.
For example, the air attack on Pearl Harbor that began at a.m.
The worst potential usability problems come when the date is written only with numbers as in the following example, because the date's interpretation will be different from one country to another. Note that this format can also be used to represent precise date and time, with timezone information Using numerical dates does have also some pitfalls with regard to readability and usability, as explained in the Date formats The W3C QA Tips are short documents explaining useful bits of knowledge for Web developers or designers, hosted and produced by the Quality Assurance Interest Group at W3C.
While the tips are carefully reviewed by the participants of the group, they should not be seen as anything else than informative bits of wisdom, and especially, they are not normative W3C technical specifications.
When dates are represented with numbers they can be interpreted in different ways.