For today's lesson, we'll learn about how to very easily setup Core Data Contexts so that we can merge in small changes. Let's first discuss what a Nested Parent Child Context Relationship is and how changes will propagate upwards to a parent context. Next, we write the code that constructs a private concurrency context ourselves, which will then allow us to set the parent to the main context. Finally, we'll have to execute a save on the main context to make sure changes are persisted all the way into Core Data. If we fail to do this, all changes are discarded upon restart of our app.