React Introduction
What is React?
React is a front-end JavaScript library.
React was developed by the Facebook Software Engineer Jordan Walke.
React is also known as React.js or ReactJS.
React is a tool for building UI components.
How does React Work?
React creates a VIRTUAL DOM in memory.
Instead of manipulating the browser's DOM directly, React creates a virtual DOM in memory, where it does all the necessary manipulating, before making the changes in the browser DOM.
React only changes what needs to be changed!
React finds out what changes have been made, and changes only what needs to be changed.
You will learn the various aspects of how React does this in the rest of this tutorial.
What You Should Already Know
Before you continue you should have a basic understanding of the following:
If you want to study these subjects first, find the tutorials on our Home page.
React.JS History
Latest version of React.JS is 19.0.0 (December 2024).
Initial release to the Public (version 0.3.0) was in July 2013.
React.JS was first used in 2011 for Facebook's Newsfeed feature.
Facebook Software Engineer, Jordan Walke, created it.