Introduction to ReactJS

Overview of ReactJS:

React.js is a JavaScript library developed by Facebook. React is a library for building composable UIs. It empowers the creation of reusable UI segments which present data that changes over time. Many people make use of React as the V in MVC. React abstracts away the DOM from you, resulting in a complex programming model and better execution. React can also render on the server using Node, and it can power local apps using React Native. React actualizes one-way reactive data stream which reduces standard and is easier to reason about than traditional data binding.

Why do people choose to program with React?

Fast - Feel quick and responsive through the Apps made in React can handle complex updates.
Modular - Allow you to write many smaller, reusable files, instead of writing large, dense files of code. Modularity of React is a beautiful solution for JavaScript's visibility issues.
Scalable - React performs best in case of large programs that display a lot of data changes.
Flexible - React approaches differently by breaking them into components while building user interfaces. This is incredibly important in large applications.
Popular - ReactJS gives better performance than other JavaScript languages due to t’s implementation of a virtual DOM.

React Features:

1. JSX − JSX is a preferable choice for many web developers. It isn't necessary to use JSX in React development, but there is a huge difference between writing react.js documents in JSX and in JavaScript.

2. Unidirectional data flow and Flux − React.js is designed in such a manner that it will only support data that is flowing downstream, in one direction. If the data has to flow in another direction, you will need additional features.

3. Components − Components are the heart and soul of React. Components (like JavaScript functions) let you split the UI into independent, reusable pieces, and think about each piece in isolation.

React Advantages:

• React.js creates its own virtual DOM. This will improve apps performance since JavaScript virtual DOM is faster than the regular DOM.
• ReactJS helps to create awesome UIs.
• Awesome for SEO - Generally have trouble in reading Javascript, React.js stands out from the crowd as you can run React.js on the server.
• Component and Data patterns improve readability which helps to maintain larger apps.
• React can be used with other frameworks.

Frequently Asked React JS Interview Question & Answers