This forum is to discuss different features/issues of Oracle Financials modules ( GL - General Ledger, AP - Accounts Payable, AR - Accounts Receivable, FA - Fixed Assets & CM - Cash Management ).
One Operating Unit is mandatory and more than one you need to create for further management and security reasons. Few modules operate at OU level so if within that module if you need partition then you need to add OU. AP, AR, CM, OM etc are examples.