diff --git a/16-markdown-preview/setup/src/index.js b/16-markdown-preview/setup/src/index.js
index 2cb1087e7..c0523f5bb 100644
--- a/16-markdown-preview/setup/src/index.js
+++ b/16-markdown-preview/setup/src/index.js
@@ -1,9 +1,21 @@
+// Importing the React library, which is essential for building React components
 import React from 'react';
+
+// Importing the ReactDOM library, which is used to render React components to the DOM
 import ReactDOM from 'react-dom/client';
+
+// Importing the CSS file to apply global styles to the application
 import './index.css';
+
+// Importing the main App component, which serves as the root component of the application
 import App from './App';
 
+// Creating the root element for rendering the React application
+// This refers to the 'root' div in the HTML file
 const root = ReactDOM.createRoot(document.getElementById('root'));
+
+// Rendering the application using the root element
+// Wrapping <App /> with <React.StrictMode> to highlight potential problems in the application during development
 root.render(
   <React.StrictMode>
     <App />