Hey y’all! It’s 2020 now and maybe some of you ask Why ReactJS Development is so popular and is it worth learning now? Let's face it - the digital world changes as we talk. Of course, it is difficult to adapt to trends in such a reality. 

However, this is exactly what the big services and applications that everyone has heard in this direction are doing. Big apps like Facebook, Instagram, Netflix and others are constantly improving their experience and adapting to new frameworks and trends. Recently, there has been a lot of discussionі around ReactJS and its impressive capabilities. Honestly, ReactJS has its pros and cons, but over the years of its existence, it has gained incredible popularity. In this article you will read about numerous benefits of ReactJS, key features and advantages in the IT industry.

In short, React is a JavaScript library for building user interfaces. Very often it is misinterpreted as a framework or programming language. React allows developers to create large web applications that can manipulate and modify data without reloading the page. Its main goal is to be fast, simple and scalable. React only applies to UI in apps. It's just a JavaScript runtime. An easy, fast and modern way to execute code on your computer.

● Facebook uses ReactJS, albeit in part. The mobile app is also built on a version of React called React Native, the essence is the same, although it is responsible for displaying iOS and Android native components instead of DOM elements. Interestingly, Facebook is where the ReactJS library was originally created, so it's obvious that they are using it.

● The role of ReactJS on Instagram is huge. Proof of this is numerous features such as geolocation, Google Maps API, search engine accuracy, and tags that fly out without hashtags. And all this is in the API of the application - which is really impressive.

● The React version works with Netflix as well - especially on their platform called Gibbon, which is used for low-end TV devices instead of the DOM used in web browsers. Netflix even posted an official blog post explaining how the ReactJS library can help to improve startup speed, performance, modularity, and other benefits. Netflix's UI engineers write this in a blog post: "A number of factors influenced our decision to adopt React, primarily: 1) launch speed, 2) performance, and 3) modularity."

● A couple of months ago, the New York Times came up with a great new project that mimics the look of the stars on the Oscars' red carpet. Obviously, this project's interface has been built into React and allows users to filter a gallery of different photos over 19 years. The re-rendering in this project is just one of the impressive features we can thank ReactJS for.

● Surprisingly (or not), Yahoo Email clients use React too. Ever since Facebook took over Yahoo!, the idea of a powerful and streamlined architecture was born, which is why React has been included to its fullest. The engineers working on the Yahoo Mail platform needed a lot of updates. Namely: independently deployable components, lower level of occurrence, independence from large libraries. They use ReactJS for the following reasons: React implements one-way reactive data flow, virtual DOM allows client and server side code execution, code in JavaScript, and the growing and active community.

● Although, there were several beta versions prior to its official launch, WhatsApp uses ReactJS to build user interfaces too.

Key Features of ReactJS:

● React gives developers the ability to work with a virtual browser that is friendlier than the real one. The React virtual browser is a kind of intermediary between the developer and the real browser.

● React allows developers to declaratively describe their user interfaces and the state model (hereinafter - state) of these interfaces. This means that instead of describing each operation with interfaces, developers only need to describe these interfaces in terms of the final state (as a function). When some state changes occur, React will update the appropriate UIs based on the changes.

● React is based on just JavaScript, there are very few APIs to learn, just a few functions and no difficulties on how to use them. Therefore, your JavaScript skills are what makes you a better React developer. No barriers to entry. A JavaScript developer can become a good React developer in a matter of hours.

● From the moment when web browsers started to understand JavaScript, we can use React to describe Web User Interfaces. I like to use the word describe in this context because this is exactly what we really do with React: we just specify what we want and React will build the user interface we want in the browser. Without React or a similar library, we would be forced to manually build user interfaces using native Web APIs and JavaScript.

● In React, we describe user interfaces using components. You can think of components as simple functions (in any programming language). We call functions with some arguments, after which they return the result to us. We can reuse functions at our discretion and form larger functions from smaller functions.

● In the browser, we need to create HTML interfaces in the Document Object Model (DOM). With React, you don't have to worry about how to display these changes and even when to make those changes in the browser; React itself will react to changes in the state and automatically update the DOM at the right time.

In the end, development productivity with ReactJS, efficiency gains, and numerous organizational benefits are all the reasons why it is so popular and why large and famous applications are upgrading to ReactJS and taking advantage of the library's benefits. And despite every “framework” update that incurs some additional costs, none of this matters much when it comes to creating the perfect user interface - whether it is a web or a mobile application.