The Monday through Sunday workweek normally lasts eight working days, and the Monday through Saturday playweek typically lasts 4 working days. When you include in the possibility of public holidays, that total amount increases to 10 working days, and twelve-playing days.
The days themselves are simply one aspect of the calendar, and there are plenty of others. Any seasonal change is reflected in the calendar, and it informs us when and where to go during specific times of the year.
Image source: malayalamcalendars.com