|
Campaign to get the Internet World to
use the
International Date Format
ISO 8601
Ever been to a webpage to see that the time-sensitive
information you are interested in is dated 03/05/01?
Is this date the 3rd of May 2001 or the 5th of March
2001 or the 1st of May 2003 and does the
01 refer to 2001 in the first two
cases?
In order to make the right choice, you must ask yourself
some questions :
- Where is the website you are visiting based?
- Is the website in a country which supports the U.S.A. style date
format (mm/dd/yy) or the European style (dd/mm/yy)?
- Which countries do officially use the U.S.A. style date
format? Is there an official list?
- Is the page author :
- American?
- European?
- Japanese?
- someone who thinks or wishes he/she was one of these
nationalities?
- one of these nationalities living in a foreign country?
- someone using a particular format because they think it is a
world standard?
- confused, and has got the numeric fields in an order different
to what they intended?
Which one is it? It could be very important to you.
The Internet is a truly International method of communicating - there
are no political or cultural boundaries drawn on the www page you call
up - the page could have been stored in the Smithsonian Institute or on
a small server in a basement in Ulan Bator, Mongolia. Often, you have no
way of telling. So, if anyone in the world can read your page, why not
ensure that any date references on that page can be read correctly and
unambiguously by that person, by using the ISO 8601:1988
International Date Format.
So what is this
date format?
CCYY-MM-DD
where CC is the
century (representing the digits used in the thousands and hundreds
components, as opposed to the actual century), YY is the year, MM is the month of the year between 01
(January) and 12 (December), and DD is
the day of the month between 01 and 28 or 29 or 30 or 31, depending on
length of month and whether it is a leap year. These dates are
using the Gregorian calendar.
For example : 2001-01-15 is the fifteenth of January
in the year two thousand and one A.D. - completely
unambiguous
Simple, isn't it?
Eleven good reasons to use
it
- language independent - a true international standard from
the International
Organisation for Standardisation (see Note 1 below)
- cannot be confused with any other popular date notations
- consistency with the common time notation system, where the
larger unit (hour) is written in front of the smaller ones (minutes
and seconds)
- easily readable and writeable by software (no month name to
number conversion necessary)
- easily comparable and sortable with a trivial string
comparison
- strings containing a date followed by a time are also easily
comparable and sortable e.g. 1996-01-15 22:45:37 with most
significant value to the left
- the notation is short and has constant length, which makes
both keyboard data entry and table layout easier
- identical to the Chinese date notation, so the largest cultural
group (>25%) on this planet is already familiar with it - so no
feeble excuses like "but no-one uses this format..."
- date notations with the order "year, month, day" are in already
widely used in Japan, Korea, Hungary, Sweden, Finland, Denmark to
name just a few. Even people in the US are already used to at
least the "month, day" ordering
- a 4-digit year representation would have avoided the Year 2000
problem. If only they had thought of that when computer
technology was being developed...
- Astronomers have been using this format for
centuries
Note 1 : there are several calendars in use
around the world using different reference points (eg. AD 1996 in the
Jewish calendar is 5757, in the Islamic calendar 1417) but whenever
any of the people using a local calendar speak to anyone outside their
calendar regime, they use the Gregorian calendar, so this can be
considered to be the international standard for date representation.
A bucket full of stuff on
calendars is available elsewhere
The International Date Format is designed for
the time-stamping of data, events and information so that anyone in the
world, of any nationality will know, without ambiguity, which date this
identifier relates to. For example : press releases, scientific papers,
sell-by/use-by dates, legal documents, any time-stamped data, important
events in the future or past.
Do you wish to download your own
copy of the full ISO8601 standard?
Unfortunately, you cannot download your own copy of the
latest version of the standard unless you pay some money to ISO.
Seems pretty daft to me - if you
want a worldwide standard to be adopted it should be freely available to
everyone who could possibly want to use it.... maybe the Internet will
change this.
Older versions are available and you can download them
from the ISO8601 group files
section.
Page last updated
2001-02-22
 
|
