What is React?

Think it like the reaction in real life. Now if I touch in the corner of your belly. What will you do? You will react right. You will laugh, or you may slide from your position, or you will be angry with me if you do not know me personally.

But in one way or another you will react. So that's it. When this reaction happens inside the web browser instead of you this calls React.

Unlike traditional web apps when you click something or drag something that instant React, that instant data fetch without reloading the webpage. Yes my friend when you can achieve this kind of behavior using a JavaScript library called React. That is React JS.