The Monday through Sunday workweek usually lasts eight working days, and the Monday through Saturday playweek normally lasts four working days. When you add in the possibility of public holidays, that total amount increases to ten working days, and twelve-playing days.
The days themselves are just one element of the calendar, and there are plenty of others. Any seasonal change is shown in the calendar, and it informs us when and where to go during specific times of the year.
Image source: a-printable-calendar.com