Study with us!

Do you want to build powerful interactive web applications that enable top websites? Get React Training and Unlock Opportunities!

Study now

What is React?

React is a component-based JavaScript library that is used to develop interactive user interfaces. In React, everything is a component and users can make changes to one component without affecting the rest of the components of the application. This feature is quite effective when implemented with real-time and much larger applications where the data changes frequently. Every time a new data is added, React would automatically update that specific component without having to reload the entire application to reflect the changes. More companies are adapting React every day and have a broad penetration across different industries. It is used by Netflix, PayPal, Apple, Instagram, Facebook, and many more companies.

Javascript Popularity

The chart shows the number of pull requests for the top 15 programming languages last year among the 337 programming languages. JavaScript has about double the number of pull requests on GitHub previous year than the second-most popular language, Python. JavaScript is the most popular language used to build applications, mobile apps, and video games.


React Growth

React is fast becoming a more popular choice for native JavaScript mobile and desktop apps. The given chart shows that that among the three frameworks – React, Angular and Vue, React has the most number of downloads last year with Angular taking the second place. The demand for Angular has been on the rise, but it is no closer to React.


React and other libraries

Even though React comes with a couple of built-in solutions such as syntactic events and local state management for interactions to happen, but they are not sufficed when building much larger applications. React is only a view-layer library and you will still need other building blocks to make your applications more specific. Some of the open-source react libraries are Create React App, Material UI, Styled Components, MobX, Enzyme, Redux.

React and other devices

React can be used to implement interfaces across multiple platforms and supports both client and server side rendering. There are many different react renders that are used by developers. The most common ones are React Native, React-Blessed, React AR, React VR, React Hardware, Victory, Ink, Spectacle and many more. React Native is one of the most popular frameworks for building native applications using JavaScript.

Subscribe our newsletter

Sign up to receive study materials and exercises!

Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

Essential React Questions and Answers

Few questions and answers you need to prepare for React interviews. If you encounter any React-related issue, feel free to contact our specialist at

1. What are the major advantages of using React?

React llows for better user experience and makes the work of developer much faster. React components can be reused, it helps save significant time. The one-direction data flow in React JS helps make the code stable. It is an open source library that means it is constantly developing and is open to contributions.

2. What are the different phases of React component’s lifecycle?

The three different phases of React component’s lifecycle are Initial Rendering Phase, Updating Phase and Unmounting Phase, particularly in that order. The first phase is when the component makes it way to the DOM. The second phase is when the component is added to the DOM, and it re-renders and updates when a state change occurs. The last phase is the one where the component is destroyed and removed from the DOM.

3. What are Keys in React and why are they so important?

Keys help keep track of the different items that have changed, added or removed from the list. Without the use of keys, React cannot know which local state corresponds to which item that is on the move. They help in checking which elements are newly inserted and make the process of reconciliation efficient.

4. Can browsers read JSX?

Browsers cannot only read JavaScript objects, and JSX is not one of them. To enable the browser to read JSX, it has to be first converted into a JavaScript object using JSX transformers such as Babel and then pass on to the browser.

5. What is React Router?

React Router is a routing library that is built over React and it helps in adding new screens and flow to the application. It syncs the URL with the data that is being displayed on the web page. It is usually used to standardize structure and behaviour.

6. Ok, great! I want to learn React! How to do it?

Learning React is not a walk in the park, but we believe that a good approach is a great start! There are a few ways to learn it, and one we could recommend is to sign up for our newsletter or look at exercises available on our GitHub and updated on a regular basis:

Duis cursus, mi quis viverra ornare, eros dolor interdum nulla, ut commodo diam libero vitae erat.

John Kowalsky

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse varius enim in eros elementum tristique. Duis cursus, mi quis viverra ornare, eros dolor interdum nulla, ut commodo diam libero vitae erat.