User:LukeSurl/First day of the week

The identity of the first day of the week varies depending between standards and/or cultures. Monday, Saturday and Sunday are each considered the first day of the 7-day week cycle in different contexts.

In the Judaic, some Christian, as well as in some Islamic traditions, Saturday is the final day of the week, thus making Sunday has the first.

Linguistics
In many languages there is an implicit or explicit order to the days of the week implied by the words used for days.

In Hebrew Sunday is called יום ראשון yom rishon, in Arabic الأحد al-ahad, in Persian and related languages یکشنبه yek-shanbe, all meaning "first".

In Greek, the names of the days Monday, Tuesday, Wednesday, and Thursday ("Δευτέρα", "Τρίτη", "Τετάρτη" and "Πέμπτη") mean "second", "third", "fourth", and "fifth" respectively. This leaves Sunday in the first position of the week count. In Portuguese, where the days from Monday to Friday are counted as "segunda-feira", "terça-feira", "quarta-feira", "quinta-feira" and "sexta-feira", while Sunday itself - similar to Greek - has the name of "Lord's Day" ("domingo"). In Vietnamese, the working days in the week are named as: "Thứ Hai" (second day), "Thứ Ba" (third day), "Thứ Tư" (fourth day), "Thứ Năm" (fifth day), "Thứ Sáu" (sixth day), "Thứ Bảy" (seventh day). Sunday is called "Chủ Nhật", a corrupted form of "Chúa Nhật" meaning "Lord's Day". Some colloquial text in the south of Vietnam and from the church may still use the old form to mean Sunday. In German, Wednesday is called "Mittwoch", literally "mid-week", implying that weeks run from Sunday to Saturday.

Slavic languages implicitly number Monday as day number one, not two. Hungarian péntek (Friday) is a Slavic loanword, so the correlation with "five" is not evident to Hungarians.

In the Maltese language, due to its Siculo-Arabic origin, Sunday is called "Il-Ħadd", a corruption of "wieħed" meaning "one". Monday is "It-Tnejn" meaning "two". Similarly Tuesday is "It-Tlieta" (three), Wednesday is "L-Erbgħa" (four) and Thursday is "Il-Ħamis" (five).

In Armenian, Monday is (Yerkoushabti) literally meaning 2nd day of the week, Tuesday (Yerekshabti) 3rd day, Wednesday (Chorekshabti) 4th day, Thursday (Hingshabti) 5th day. Saturday is (Shabat) coming from the word Sabbath or Shabbath in Hebrew, and "Kiraki" coming from the word "Krak" meaning "fire" is Sunday, "Krak" describing the sun by fire. Apostle John also refers to the "Lord's Day" (in Greek, Κυριακή ἡμέρα, "kyriake hemera" i.e. the day of the Lord) in Rev. 1:10, which is another possible origin of the Armenian word for Sunday.

However, in many European countries calendars almost always show Monday as the first day of the week, which follows the ISO 8601 standard.

In the Persian calendar, Sunday is the second day of the week. However, it is called "number one" as counting starts from zero; the first day - Saturday - is denoted as 00.

ISO 8601
The international standard ISO 8601 for representation of dates and times, states that Sunday is the seventh and last day of the week. This method of representing dates and times unambiguously was first published in 1988.