Production Calendar 
You can use this function to set up a calendar specifying days on which you plan to manufacture a product (workdays).
The system uses this calendar for reporting purposes. Reports use the calendar to assign production to specific dates and shifts.
Workdays
Days on which a product can be manufactured at a particular site
A workday type defines the shifts that make up the specified production day and the hours for those shifts.
Rules for Day Type Definition
As you define production day types in Production Shift Maintenance, adhere to the following rules:
The shifts in a given day type definition can overlap.
A workday type cannot be longer than 24 hours. The 24 hour period does not need to start and end at midnight.
A workday type applies across a specific site (to all work centers in the site).
Example
Assume that days at a given site are one of the following types:
A typical weekday, consisting of three production shifts.
A typical weekend, consisting of one production shift; only a day of the weekend.
A holiday with one shift only starting at a different time from that of the shift on a typical weekend.
In such a case, you need to define three production day types.
If no production takes place on some days, you can leave those days blank on the production calendar. You can also define a production day type (for example, one named NOPRODUCTION) to indicate that no production is planned on some days.
Activities
You define workday types in Production Shift Maintenance (see Production Shift Maintenance).
You apply the production day types to calendar days in Production Calendar Maintenance to generate a production calendar (see Production Calendar Maintenance).