Earlier in this series, I mentioned that the coordinator pattern works well with the Model-View-ViewModel pattern. The resulting pattern is commonly referred to as MVVM-C or the Model-View-ViewModel-Coordinator pattern. In this episode, we refactor the PhotosViewController class. It currently uses the Model-View-Controller pattern. We update the implementation of the PhotosViewController class to use the Model-View-ViewModel pattern instead. I won't cover the details of the MVVM pattern in this episode, though. The MVVM pattern is covered in detail in Mastering MVVM With Swift.