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What is React.js and why it’s worth to learn?

Deciding to change your career and get into a tech market as a coding specialist is the first step to a great adventure that you start now. After some research, you decided to build websites and web apps, it seems easy for beginners and very in demand, so that’s the thing you want to jump in.

You already know that HTML and CSS are the total basics you have to learn, later Javascript is in the queue of the skills to get. But to be sure you’ve had the proper knowledge to get a position, you take a quick look at a few job boards and job offers to make your to-do list fully complete.

In most of the offers, you see a new skill popping up, React JS. Is it another programming language, or maybe just a coding software? What is it used for, and where? What is React JS?

This is the question I’m going to answer in this article, describing this popular library, its main features, and advantages, projects made using React JS. You will find out if you should learn it, selecting a web developer or front-end developer career path.

Let’s get into it!

What is React JS?

React JS is an open-source, component-based Javascript library, which is used to build UI specifically for single-page applications. It’s one of the most popular Javascript libraries used to build apps front-end right now. Facebook developers created ReactJS in 2011 and used first in the Facebook app, and until today it has a huge community supporting it and lots of resources to learn it.

But, let’s start from the beginning as you may not know what is Javascript library and why do we use them.

Javascript is a programming language used to create dynamic elements on the website or web app. Almost all modern browsers support Javascript. Entering any webpage, it has lots of features written in Javascript, like form validation, advanced animations, popups, etc. Javascript is used to build web apps and pages with client-side scripting.

Now, let me explain what the Javascript library is and why we use it. JS library is a pre-written Javascript code that makes the development of apps easier and faster. It consists of ready components, functions, and patterns, which can be used to accomplish specific programming tasks. In many cases, it also helps to keep our applications more secure and more efficient. Javascript frameworks are used to decrease the amount of coding and reduce the cost of app development, as libraries are mostly open-source and free.

Okay, we discussed what Javascript and Javascript library is. Now let’s get back to ReactJS and find out what is it used for and why it’s so popular.

ReactJS features

Before ReactJS came alive, developers used jQuery or vanilla Javascript to create the UI (user interface). Every developer has his or her way of coding in a vanilla programming language, which may bring lots of bugs and troubles for new people in the team. Using a library like ReactJS may help to organize the development and bring even more advantages with features that make ReactJS such a popular and widely used library. Let’s take a closer look at these features.

Virtual DOM

If you are using pure Javascript, your DOM object will re-render every time any change will be done in HTML elements. It’s fine if you have a static website where not too much happens; the performance is safe. But in the case of dynamic web apps that have lots of user interaction elements, it doesn’t work so good. The performance of the application goes down significantly.

Creators of ReactJS decided to handle this issue, and they created a Virtual DOM. When changes are made in the DOM, ReactJS creates a copy, called Virtual DOM. This copy is compared with the normal DOM, and only the element which is different is re-rendered. It takes less computing power, and loading time, that’s why it’s a good improvement.


In ReactJS, JSX is used for creating templates instead of HTML. JSX is a kind of extension of Javascript, and it allows us to use HTML tags inside the Javascript code. It’s used to create templates in ReactJS.

React Native

While using ReactJS, it’s very close to switching to React Native, technology to create front-end for mobile applications. It provides a rich library of ready components for IOS and Android, as well. By learning and using ReactJS, you can easily switch to React Native and create native mobile apps.

Big projects using ReactJS

ReactJS is a very popular technology is used not only to create your startup ideas, but also huge companies use this technology for huge projects. Let’s take a look at the most popular apps created with ReactJS.

New York Times
Yahoo! Mail

As you can see in the previous list, huge projects were created using ReactJS, this may also be a reason why it’s such popular.

Why is ReactJS worth learning and using?

After a quick introduction to what ReactJS is and what are its main features, let’s try to answer if it’s worth to learn it. Taking into consideration that there are a lot of open-source libraries and frameworks on the market to create front-end, it may be confusing which one you should select.

I think if you are planning a career as a front-end developer, it’s definitely worth to know. Remember that every task needs right tools to do it right, and in case of creating UIs, selecting React JS may be the right choice, as that’s what React JS actually is, it’s a UI library.

React is a framework with a low entry threshold, and its learning curve is quite low, which makes it friendly for beginners. Also, the huge community and a lot of resources to learn makes ReactJS very competitive at the start point. Having the knowledge of HTML, CSS, and Javascript can help to learn React and create an amazing Single Page Applications very quickly.

Another thing which makes React JS worth to learn technology is the number of job offers on the market. Filtering job boards by the skills will show you how many React developers companies need. It’s one of the most in-demand technology in the front-end field right now, so it’s definitely a great skill in your CV.


ReactJS is one of the most popular Javascript libraries, and since 2011 it grows very fast, and it’s updated by Facebook to make it better and better. During that time, it got about 140k stars on Github, which testifies that developers and companies really like this technology.

If you are looking for another technology to learn and improve your skills set, React may be a great choice, if you are not sure, just try it out and check it if you find the React way of coding your favorite.

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Top comments (6)

esdee_reign profile image
Snehdeep Singh

Thank you for the effort!! :)

ramrachai profile image

I started to learn recently. Can you please give me a quick suggestion on how to learn Reactjs properly and efficiently ?

duomly profile image

For me, the best way of learning new tech is always learning the basics, and code as much as possible.

esogargar profile image
Israa Gargar

Thanks for the info and the tip 🙋💜

asuhel profile image
Aun Suhel

I found the information interesting... but i have to say...the author hasnt taken the time or effort to write fluently. It feels like its the work of an amateur. Expect high quality articles in the future

paulcook159 profile image
Paul Cook

Useful and informative article. I found one blog on topic why Reactjs Is Popular, check out here