We started off by talking about the patterns that make up RxJS. We continued by describing its core concepts. This was followed by describing how and when it was necessary to create your own Observable, opt for one of RxJS many creation operators, or rely on the Angular framework to do this job for you. We briefly discussed the importance of cleaning up after your Observable and when it was a good idea to do so.

Lastly, we took on the task of implementing part of the RxJS core to gain a deeper understanding of its core concepts and how it all came together. This has hopefully given you a pretty solid foundation and in-depth understanding of RxJS as we venture into the next chapter, which will cover more operators, and some more advanced concepts.