The Store Manager Inventory module uses Inventory Periods, periods of time which run from one accounting reference date to the next (usually one week). In these periods, all posted batch transactions are considered together, providing a snapshot of your business activities for reporting purposes.
Report Periods use and combine one or more Inventory Periods for reporting purposes.
There are three elements in the Period screen: Periods, Fiscal Year, and Report Periods. Follow the links for information on working with these components: