The following example illustrates a BPM workflow.In a content management
business process, an editor edits the content and the manager approves the
content.If you define editing of the content as a unit of work and approving the
job as another unit of work, then the editing job needs to happen first for the
approval job to start. Further, if the editing job fails, the approval job can't
start.
http://www.freewebs.com/business-process-management/Workflow.html