In this lecture you will learn what an Observable is and where and when to use it. An observable is not native to angular or JavaScript. It is provided by yet another JavaScript library RxJS.

We use Observables to deal with asynchronous operations and asynchronous data. In this lecture you will learn:
1. What is an Observable?
2. Difference between a Promise and an Observable
3. How to create an Observable?
4. How to use the data emitted by an Observable.