1179: ISO 8601

2013-02-27T17:38:48Z

MarkAtwood:

{{comic
| number = 1179
| date = February 27, 2013
| title = ISO 8601
| image = iso_8601.png
| titletext = ISO 8601 was published on 06/05/88 and most recently amended on 12/01/04.
}}

==Explanation==
{{w|Public service announcement}}: The two most commonly used date formats in the world are {{w|Date format by country|dd.mm.yyyy and mm/dd/yyyy}} (the symbols separating the values, as well as the year being 2 or 4 digits notwithstanding). These differences are often causes for debate. However, the comic explains that the {{w|International Organization for Standardization}} (ISO) has standardized dates in the yyyy-mm-dd format, in its {{w|ISO 8601}} standard.

The comic then lists many formats as "discouraged". This list starts with commonly used formats, which include the two above as well as other commonly used ones, such as dd/mm/yy. However the list then starts listing formats ranging from uncommon to absurd, such as writing the date partly in Roman numerals and painting the date in m/d/yy format with white paint onto a hissing black cat.

The title text mentions two dates in either the dd/mm/yy format or the mm/dd/yy format, but because the day values in both dates are less than 13, the format used is ambiguous. In yet another date format, the standard was published on 5 June 1988 and amended on 1 December 2004. It is notable that the dates in the title text are not in ISO 8601 format, contradicting the advice in this comic, adding a level of metahumor, and also demonstrating an advantage of ISO 8601 over the formats used.

The other mentioned formats are:

{| class=wikitable
! Date !! Explanation
|-
| 02/27/2013
| MM/DD/YYYY, used mostly in the US
|-
| 02/27/13
| MM/DD/YY
|-
| 27/02/2013
| DD/MM/YYYY, used e.g. in South America, Canada and Europe
|-
| 27/02/13
| DD/MM/YY
|-
| 20130227
| YYYYMMDD
|-
| 2013.02.27
| YYYY.MM.DD
|-
| 27.02.13
| DD.MM.YY, e.g. in Germany
|-
| 27-02-13
| DD-MM-YY
|-
| 27.2.13
| D.M.YY
|-
| 2013. II. 27.
| YYYY. MM. DD., month as {{w|Roman number}}
|-
| 27⁄2-13
| D⁄M-YY
|-
| 2013.158904109
| Year and decimal fraction of year – 58/365, February 27 being the 58th day of the year. This representation marks the end of that day.
|-
| MMXII-II-XXVII
| Year-month-day in Roman numerals, but for '''2012'''-02-27
|-
| MMXII [and] LVII [over] CCCLXV
| Year and 57/365. This representation marks the start of the day, which is 57 days after the year started. Probably should have been 2013 instead of 2012; if 2012 were intended, this should have been MMXII[and]LVII[over]CCCLXV'''I''', as 2012 was a leap year.
|-
| 1330300800
| {{w|Unix time|UNIX Timestamp}}, but for '''2012'''-02-27
|-
| ((3+3)×(111+1)-1)×3/3-1/33
| Year/month/day with the parts written as arithmetic expressions
|-
| 27 [''over''] 02 [''over''] 2013
| An obfuscated date format not used ordinarily. This can be considered a compromise between the different formats: Since we cannot agree on which position in the date the day, month and year parts shall be, we just write them all in the same place. We don't even need separators, which we cannot agree on either.
|-
| 10/11011/1101
| MM/DD/YY in {{w|Binary number|binary}}
|-
| 02/27/20/13
| MM/DD/YY/YY
|-
| 0 [2,5] 1 [3] 2 [1,6,7] 3 [4] 7 [8]
| The big 01237 digits are used at positions listed above and below: 0 is used at positions 2 and 5, 1 is used on position 3, etc.; the result being 20130227
|-
| ''A cat, with the numerals'' 2-27-13 ''painted on it, going'' HISSSS
|
|}

==Transcript==
:Public Service Announcement:

:Our different ways of writing dates as numbers can lead to online confusion. That's why in 1988 ISO set a global standard numeric date format. This is '''''the''''' correct way to write numeric dates:

:2013-02-27

:The following formats are therefore discouraged:
*02/27/2013
*02/27/13
*27/02/2013
*27/02/13
*20130227
*2013.02.27
*27.02.13
*27-02-13
*27.2.13
*2013. II. 27.
*27⁄2-13
*2013.158904109
*MMXII-II-XXVII
*MMXII [and] LVII [over] CCCLXV
*1330300800
*((3+3)×(111+1)-1)×3/3-1/33
*27 [''written on top of''] 02 [''written on top of''] 2013
*10/11011/1101
*02/27/20/13
*0 [2,5] 1 [3] 2 [1,6,7] 3 [4] 7 [8]
*''A cat, with the numerals'' 2-27-13 ''painted on it, going'' HISSSS

{{comic discussion}}

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1179: ISO 8601