What is retained logic and progress override and can you give me an example?

When you choose Retained Logic, the remaining duration of a progressed activity is not scheduled until all predecessors are complete. When you choose Progress Override, network logic is ignored and the activity can progress without delay. Retained Logic - Project A has relationships. If you choose retained logic, P6 abides by those relationships and schedules accordingly. Progress Override- Project A has relationships, but they are ignored when you progress activities.