Composition and child view controllers

As you saw previously, you should always pay attention to the view life cycle and never rush it. Another thing that we need to pay attention to is the size of our view controller. Smaller view controllers are beneficial for the following:

All of these features come for free when you compose your view controllers accordingly.

Composing view controllers implies using a custom container view controller. The container view controller will be responsible for maintaining the hierarchy of controllers, as well as the views provided by those child view controllers.