Polyfills are additional scripts that provide compatibility for features or APIs that are not supported by all browsers. These scripts are automatically included in an Angular application during the build process to ensure that the application can run on a wide range of browsers, including older versions. Here's an example to illustrate the usage of polyfills in an Angular application: 1. Open the "polyfills.ts" file: In your Angular project, locate the "polyfills.ts" file, which is usually located in the "src" folder. This file contains the configuration for the polyfills. 2. Uncomment or add the required polyfills: Inside the "polyfills.ts" file, you'll find a section with a list of polyfills that can be uncommented or added as needed. Each polyfill corresponds to a specific feature or API that may not be supported by all browsers. For example, if you need to support older browsers that lack support for certain JavaScript features, you can uncomment or add the polyfill for the specific feature. Let's say you want to provide support for the `Array.from` method, which might not be available in all browsers. You can uncomment or add the following line:

   // Uncomment below to enable support for 'Array.from' in older browsers
   // import 'core-js/es/array/from';

This line imports the polyfill from the "core-js" library to ensure that the `Array.from` method works in browsers that don't support it natively. Similarly, you can uncomment or add other polyfills based on the features or APIs you need to support. 3. Build and deploy the application: After configuring the required polyfills in the "polyfills.ts" file, you can proceed to build and deploy your Angular application as usual using the Angular CLI or your preferred build process. During the build process, Angular will bundle the application along with the specified polyfills. These polyfills will be automatically loaded in the browser alongside your application code. Conclusion: By including the appropriate polyfills, your Angular application can leverage modern features and APIs while maintaining compatibility with a wider range of browsers, including older versions. The polyfills ensure that the application behaves consistently across different browsers, providing a smooth and functional user experience. Remember to review and update your polyfills periodically to ensure compatibility with evolving browser standards and to optimize the performance of your application.