JSX stands for JavaScript XML. It is a syntax extension for JavaScript that is commonly used in React.js, a popular JavaScript library for building user interfaces. JSX allows developers to write HTML-like code directly within JavaScript, making it easier to define and render user interface components.

With JSX, we can create React elements by combining JavaScript expressions with HTML-like syntax. These elements can represent UI components, which can be rendered to the DOM (Document Object Model) or used as building blocks for more complex UI structures.

The example of JSX Code in React JS is mentioned below -

import React from 'react';

  const App = () => {

    const name = 'John Doe';
  
    return (
      <div>
        <h1>Hello, {name}!</h1>
        <p>Welcome to my React app.</p>
      </div>
    );
  };
  
  export default App;

In the above code, the App component is defined using a functional component syntax. Within the return statement, you can see how JSX is used to define the structure and content of the component. The curly braces {} are used to embed JavaScript expressions, allowing you to dynamically insert values, such as the name variable in the example.

JSX elements are transformed into React elements during the build process, using tools like Babel. The resulting React elements are then rendered to the DOM or used within other React components.