What is React.js?

What does a React developer do?

From conception to testing, a top-notch React developer can help you build interactive components for your website or web applications using the React development concepts.

Open Source

Let’s first explore the interesting world of React. Alternately spelled as React.js or ReactJS, React is an open-source JavaScript library that specializes in building UIs (user interfaces).

User Interface

Simply put, UI is a term that describes any element that allows users to interact and communicate with the information saved in a device (laptop, tablet, smartphone, etc.). User interface is the primary point-of-contact between humans and modern computers.


Before React.js was introduced, developers back then were stuck building UIs using JavaScript or jQuery. This meant that the development process took longer with more room for errors and bugs. To solve this problem,Facebook engineer Jordan Wilke created FaxJS (first prototype) in 2011.


React makes it simple and easy to build websites and apps, create UI test cases, reuse existing codes on website to its mobile counterpart, and improve UI and performance of web applications. It’s versatile enough to use where JavaScript is required.


Today, more and more enterprises benefit from ReactJS, a testament to its burgeoning popularity in software development. Some of the high-traffic websites that use React are Instagram, Uber, and Reddit.


Along with the upswing in React usage, is the surge in demand for a React.js developer. A highly-skilled React developer is involved in the entire stages in the development and maintenance of user interface components.