To access the Vacation Types master data, go to HR & and Payroll > See Also > Vacation Types. This master data is available only if the HR and Payroll module is enabled on Administration > Settings > HR and Payroll form.
Vacation types are used to calculate the accrued vacation days and vacation pay for all employees. 
The Vacation Types list
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Initially, there are no vacation types in the system database. To add a new vacation type, click the Create button on the toolbar. To learn more about how to create them, see Adding a Vacation Type.