Names of the days of the week the "first day". This convention is also found in some Austronesian languages whose speakers were converted to Christianity by European missionaries. In Slavic languages, some of the names correspond to numerals after Sunday: compare Russian "vtornik" "Tuesday" and "vtoroj" "the following", "chetverg" "Thursday" and "chetvertyj" "the fourth", "pyatnitsa" "Friday" and "pyatyj" "the fifth"; see also the Notes. In Standard Chinese, the week is referred to as the cycle of the stars (). The modern Chinese names for the days of the week are based on a simple numerical sequence. The word for "week" (which is literally translated to "star day")
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