In this chapter, we took a deep dive into RxJava, a port form Microsoft's Reactive Extensions from .NET. We learned about its main abstraction, the observable, and how it relates to iterables.

We also learned how to create, manipulate, and combine observables in several ways. The examples shown here were contrived to keep things simple. Nevertheless, all concepts presented are extremely useful in real applications and will come in handy for our next chapter, where we put them to use in a more substantial example.

Finally, we finished by looking at error handling and backpressure, both of which are important characteristics of reliable applications that should always be kept in mind.