The workweek and weekend are those complementary parts of the week devoted to labour and rest, respectively. The legal working week (British English), or workweek (American English), is the part of the seven-day week devoted to labour. In most of the Western world, it is Monday to Friday; the weekend is Saturday and Sunday. A weekday or workday is any day of the working week. Other institutions often follow the pattern, such as places of education.

In some Christian traditions, Sunday is the “day of rest and worship”. Jewish Shabbat or Biblical Sabbath lasts from sunset on Friday to the fall of full darkness on Saturday; as a result, the weekend in Israel is observed on Friday–Saturday. Some Muslim-majority countries historically had a Thursday–Friday or Friday–Saturday weekend; however, recently many such countries have shifted from Thursday–Friday to Friday–Saturday, or to Saturday–Sunday.