Under the hood, JSX gets transformed into JavaScript function calls to React.createElement().
Each JSX element is compiled into a call that creates a JavaScript object describing what should appear on the screen — this is called a React Element (not a real DOM node yet). React uses these elements to build and manage a Virtual DOM, which it compares with the actual DOM to efficiently update only the necessary parts.

Example: JSX:

<button>Click Me</button>

After Babel transformation:

React.createElement('button', null, 'Click Me');

This way, React maintains a lightweight representation of the UI without needing the browser to understand JSX directly.

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