RxJS stands for Reactive Extensions, which is a modular library that enables reactive programming, which itself is an asynchronous programming paradigm and allows for manipulation of data streams through transformation, filtering, and control functions. You can think of reactive programming as an evolution of event-based programming.
Transform data using RxJS
Understanding Reactive programming
In Event-Driven programming, you would define an event handler and attach it to an event source. In more concrete terms, if you had a save button, which exposes an onClick event, you would implement a confirmSave function, which when triggered, would show a popup to ask the user Are you sure?. Look at the following figure for a visualization...