The workweek and weekend are the complementary parts of the week dedicated to work and rest. The legal working week (British English) or workweek (American English) is the seven-day period devoted to labour. Monday through Friday in most of the Western world; Saturday and Sunday are weekends. A weekday, also known as a workday, is any day of the working week. Other institutions, such as educational institutions, frequently follow the pattern. Sunday is a “day of rest and worship” in some Christian traditions. The Jewish Shabbat, also known as the Biblical Sabbath, lasts from sunset on Friday to the fall of full darkness on Saturday; thus, the weekend in Israel is observed from Friday to Saturday. Some Muslim-majority countries used to have a Thursday-Friday or Friday-Saturday weekend; however, many of these countries have recently switched from Thursday-Friday to Friday-Saturday or Saturday-Sunday.
The Christian Sabbath was only one day per week, but in the twentieth century, the preceding day (the Jewish Sabbath) became a holiday as well. Following changes in employer expectations, this shift has been accompanied by a reduction in the total number of hours worked per week. The modern concept of the “weekend” arose in the early nineteenth century in the industrial north of Britain, and was originally a voluntary arrangement between factory owners and workers allowing Saturday afternoon off from 2pm in exchange for staff being available for work sober and refreshed on Monday morning. The Amalgamated Clothing Workers of America Union was the first to successfully demand a five-day work week in 1929.