This tab contains information about type of vacations granted to the employee within this employment contract. There can be listed multiple vacation types, however, only one type can be selected as Main vacation.
The list of vacation types assigned to the employee is used by month-end-closing service tool (if the Calculate Vacation Days option is selected for this process on the Accounting > Service Tools > Month-End Closing form) for automatic calculation of the number of vacation days available for this employee after the first year of service at this month's end. For example, if the employee has the main vacation of 24 days per year, each month the system will be adding 2 days (24 days per year/12 month) to accrued vacation days available for the employee.
Before you fill out this tab make sure that all the vacation types applicable to this employment contract are defined on the HR and Payroll > See Also > Vacation Types form. For details, see Adding a Vacation type. 
The "Employment contract (create)" form. The Vacations tab
To add a new line to the list, click Add on the toolbar.
In the Vacation Type column, select the type of vacation applicable to the employment contract.
Specify the duration of vacation in a year in the Days per Year column.
In the Main Vacation column, notice a check box that is selected only for the vacations of the Main type. There can be only one main vacation type and, optionally, multiple other vacation types.