RxJS Quick Overview

What is RxJS ?

RxJS stands for Reactive Extensions for JavaScript, which is a the javascript implementation of ReactiveX API. It brings the concept of "reactive programming" to the JavaScript applications for composing asynchronous and event-based programs by using observable sequences.

It is very important to cover the basic terminology, and its corresponding functionality of RxJS before proceeding to real examples-

Stream:- A stream is a sequence of data elements made available over time.

Observable:- An observable is a function which produces a stream of values to an observer over time. It can have multiple observers.

Observer:- The When subscriber of an observable, you are an observer.

Subscription:- It is the link between an observable and an observer. A subscription object is returned when we invoke the subscribe() method on an Observable.

Subject:- It is a special type of observable, which is the only way of multicasting a value or event to multiple Observers. It inherit all the methods and properties of an observable, because Subject class extends Observable. So, a subject is both an observable and an observer. As an Observer, it can subscribe to Observables, and as an Observable it can produce values and have Observers subscribe to it.

Operators:- It is a function which alter the the way Observables emit values.