The Monday through Sunday workweek typically lasts 8 working days, and the Monday through Saturday playweek normally lasts four working days. When you include in the possibility of public holidays, that overall quantity increases to 10 working days, and twelve-playing days.
However the days themselves are just one element of the calendar, and there are a lot of others. The months of the calendar represent various seasons, and the time between each of those months provides us the seasonal cycle. At the start of spring, the temperature level is high and the days are warm, while at the end of winter the air is cold and the days are cold. Every season has its own unique time associated with it, and the calendar helps us track all of those shifts. Any seasonal modification is shown in the calendar, and it tells us when and where to go during specific times of the year.
Image source: printablethecalendar.com