The weekdays and weekend are the complementary parts of the week devoted to labour and rest, respectively. The legal weekdays, or workweek, is the part of the seven-day week devoted to working. In most of the world, the workweek is from Monday to Friday and the weekend is Saturday and Sunday. A weekday or workday is any day of the working week. Other institutions often follow this pattern, such as places of education. The constituted weekend has varying definitions, based on determined calendar days, designated period of time, and/or regional definition of the working week. Sometimes the term "weekend" is expanded to include the time after work hours on the last workday of the week.

Saturday is the day of the week between Friday and Sunday. No later than the 2nd century, the Romans named Saturday diēs Sāturnī for the planet Saturn, which controlled the first hour of that day, according to Vettius Valens. The day's name was introduced into West Germanic languages and is recorded in the Low German languages such as Middle Low German satersdach, saterdach, Middle Dutch saterdag, and Old English Sæternesdæġ, Sæterndæġ or Sæterdæġ.