Code-splitting is a technique that allows you to divide your JavaScript code into smaller chunks that can be loaded and executed on demand. When done properly, this technique can significantly improve your React app's performance by reducing the initial load time and improving the overall user experience.

One of the main benefits of code-splitting is that it reduces the amount of code that needs to be loaded when a user visits your app for the first time. Instead of loading all of your app's code at once, code-splitting allows you to load only the essentials, such as your app's landing page and navigation elements. This means that the user can begin interacting with your app faster, without having to wait for all of the code to load.

As the user navigates through your app, additional code can be loaded on demand. For example, if the user clicks on a tab that requires a specific component or functionality, that code can be loaded at that time, rather than being loaded at the beginning. This helps reduce the overall load time and improve the user experience.

To implement code-splitting in your React app, you can use tools like Webpack or React.lazy. These tools allow you to split your code into individual chunks, which are loaded as needed by the app. Additionally, React.lazy allows you to lazy-load components, which means that they are only loaded when they are needed.

By implementing code-splitting in your React app, you can reduce the initial load time, improve the overall user experience, and create a more performant app.