What is React.js? And is it listed as a Front-End framework?

React is a JavaScript library. It’s not a framework. It’s not a complete solution and we’ll often need to use more libraries with React to form any solution. React does not assume anything about the other parts in any full solution. It focuses on just one thing, and on doing that thing very well.

The thing that React does really well is the second part of the definition: building User Interfaces. A User Interface is anything we put in front of users to have them interact with a machine. User Interfaces are everywhere, from the simple buttons on a microwave to the dashboard of a space shuttle. If the device we’re trying to interface can understand JavaScript, we can use React to describe a User Interface for it.

For more, Open the following three links. It will surely clarify your doubt

First Link

second link

Third link