React, also known as React.js or ReactJS, is a free and open-source front-end JavaScript library that is used for building user interfaces, particularly for single-page applications. It allows developers to create large web applications that can update and render efficiently without reloading the page. The main purpose of React is to be fast, scalable, and simple. It works only on user interfaces in the application, which corresponds to the view in the Model-View-Controller (MVC) template, so it can be used with a variety of other libraries or frameworks, such as Angular JS in MVC.
React was originally created by Jordan Walke, a software engineer at Facebook, and it was first deployed on Facebook's newsfeed in 2011 and later on Instagram in 2012. It is maintained by Meta (formerly known as Facebook) and a community of individual developers and companies.
React encourages the creation of reusable UI components, which present data that changes over time. It makes use of a virtual DOM, which is a lightweight copy of the actual DOM. This means that when a component’s state changes, React first changes the object in the virtual DOM. Then, the React-DOM compares the virtual DOM with the actual DOM and updates the actual DOM with only the changed elements, rather than re-rendering the entire page. This selective rendering provides a major performance boost and leads to a more ...
