Friday recognize the days after. In some Islamic countries, the week begins on Sunday and ends on Saturday, just like the Jewish week and the week in some Christian countries. The week begins on Saturday and ends on Friday in most other Islamic countries, such as Saudi Arabia, Somalia, and Iran. Friday is also the day of rest in the Bahá'í Faith. In some Malaysian states, Friday is the first week-end day, with Saturday the second, to allow Muslims to perform their religious obligations on Friday. Sunday is the first working day of the week for governmental organisations. Jewish Sabbath begins
Determination of the day of the week day of the week begins by starting from an ‘anchor date’: a known pair (such as January 1, 1800 as a Wednesday), determining the number of days between the known day and the day that you are trying to determine, and using arithmetic modulo 7 to find a new numerical day of the week. One standard approach is to look up (or calculate, using a known rule) the value of the first day of the week of a given century, look up (or calculate, using a method of congruence) an adjustment for the month, calculate the number of leap years