The international standard "O 860 1" of the International Organization for Standardization, entitled "Data storage and exchange form, information exchange, date and time expression", stipulates that every calendar week begins on Monday and Sunday is the seventh day.
Calendar week and day symbols:
You can use two digits to represent the calendar week in a year and one digit to represent the date of the calendar week, but you should add a capital letter w before the calendar week. For example, May 3, 2004 can be written as 2004-W 19- 1 or 2004W 19 1.
However, 2005-W0 1 1 started from 65438+20051October 3, and the first few days belonged to the 53rd calendar week of last year. Every calendar week begins on Monday, and Sunday is the seventh day.
Extended data:
The origin of the week:
Zhou originated in Babylon as a time period. At present, the system of seven days a week, which is widely practiced all over the world, was first formulated by the Roman emperor Constantine the Great. On March 7th, 32 1 year, he officially announced a seven-day week, and this system has been in use ever since.
In China, when Christianity spread in China in the late Ming and early Qing Dynasties, Zhou gradually became known. After the use of the Gregorian calendar was stipulated in the Republic of China, the week gradually became popular.
The origin of the week should be the cycle connected with the moon, because seven days is about a quarter of the moon's week.
Baidu encyclopedia -ISO 860 1
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