Over the last few years, JavaScript has become one of the most used languages, and you have already heard of the term reactive in the world of JavaScript, both in a backend and a frontend context.

So, What exactly is reactive programming?—It's a programming paradigm that has asynchronous data streams at its core. The data flows through various parts of the program in the form of a message. The message is produced by a Producer and works in a fire-and-forget manner in which the program produces a message and forgets it. The Subscriber who has subscribed (shown interest) to such messages, gets the message, processes it, and passes on the output as a message for other parts of the program to consume.

In the world of databases, NoSQL presented a huge shift from relational databases. Similarly, this programming paradigm is a huge shift from the conventional programming paradigm (imperative programming). The good thing is that without much knowledge, you have already been coding a bit of reactive code in your day-to-day coding life. Wherever you see the word stream, you are indirectly using a piece of reactive code. Such programming has a name of its own and this aspect has become more mainstream in the industry. Many languages understand the advantages this brings and they have started to natively support this paradigm of programming.