In this chapter, we learned about the ember-data library. We learned how easily and effectively the ember-data library design patterns streamline, and how the application communicates with the backend API. We started by defining our own model objects that extend the Ember Data's DS.Model class. Then, we considered how to define relationships between our model classes. After defining these relationships, we looked at the identity map provided by the ember-data library, the DS.Store class. We also learned about the optimization brought in by the data store. After looking at the store, we learned how to create, find, and modify the objects, or records of our model classes. Then, we looked at the default adapter and serializer provided by the ember-data library. We also learned how to customize the adapters according to the API we are integrating with. In the end, we looked at an example application that uses ember-data to create and fetch records from the API server. In the next chapter, we will talk about building reusable view components in Ember.js.