Understanding the Importance of Default Export when using React.lazy()

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Lazy loading is a technique used to optimize the performance of web applications by deferring the loading of certain resources, such as images, scripts, and even components, until they’re actually needed. One way to implement lazy loading in a React application is to use the React.lazy() function and the import() function.

The React.lazy() function allows you to load a component lazily, or on demand, only when it's actually needed. The import() function is used to load the module containing the component. Together, these two functions allow you to split your code into smaller chunks, which can be loaded asynchronously, improving the perceived performance of your application.

Here’s an example of how you might use React.lazy() and import() to lazy load a component:

import React, { lazy, Suspense } from 'react';

const MovieDetails = lazy(() => import('./MovieDetails'));

function App() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <MovieDetails />
      </Suspense>
    </div>
  );
}

export default App;

In this example, we’re using React.lazy() to load the MovieDetails component lazily. The import() function is used to load the module containing the MovieDetails component. The Suspense component is used to handle…