SAP Business Workflow respond to errors and exceptions in other, existing business processes. You can start a workflow when predefined events occur, for example an event can be triggered if particular errors are found during an automatic check.
PLease check this link for the WF.
Our Scenario: We wanted the sales person to be informed when a internet order was created. So we created a WF which triggers upon internet order creation and this WF will send a mail to sales person along with the ORDER# for him to take furture action.