When they're done, the workflow engine finds out what the next tasks are and takes the project on to the employees responsible. Each kind of case will have its own workflow process. Let's walk through it and explain it in detail. The circles are called places and represent the inboxes in the office-metaphor. The rectangles are called transitions and represent the tasks to be performed.
Places are inactive .
All the places do is hold tokens representing the state of the process. If, for example, there's a token in place D above, then that means we're ready to pack the order. Transitions are active . When this happens, the transition is said to fire . Transitions can only when there's at least one token in each input place .