Timing diagrams are a special purpose diagram focusing on the timing of events over the life of an object or objects.

A timing diagram is useful for showing the interaction of objects and the timing constraints between state changes for those objects along a precise timing axis.

They are a complement to the state machine diagram when event timing is a critical requirement to the successful operation of the system, such as for real-time and embedded applications.

Timing diagrams are helpful for sorting out race conditions, priority inversions, deadlocks, and other communication issues.