In this lesson, let's cover some more abstract topics related to code architecture. These two topics will be View Model View State and Reactive Programming. For those that are unfamiliar with these concepts, it'll sound somewhat intimidating at first but in reality its not too complicated. First we'll identify the areas of our code in which we can apply the abstraction. Next I'll go over how we can pull out some logic and plop it inside of our View Model that is supposed to keep track of the state of our views.