One of the challenges of diving deeper into RxJS, or Reactive Extensions for JavaScript, is the terminology. We may know the basics of using RxJS, but to really understand how it works, we need a firm grasp of its vocabulary.
Let’s focus on answering these questions:

• What is a higher-order Observable?
• What are inner and outer Observables?
• And what is the purpose of a higher-order mapping operator, such as mergeMap or switchMap?

By mastering these concepts, we can better leverage RxJS to build more declarative and reactive Angular applications.

Find the full post here: https://blogs.msmvps.com/deborahk/higher-order-observable/

To learn more about RxJS, check out my Pluralsight course: “RxJS in Angular: Reactive Development”. You can find it at this URL: https://app.pluralsight.com/library/courses/rxjs-angular-reactive-development