Push notifications are a crucial feature for modern applications, enabling direct and efficient communication with users by delivering timely alerts and updates. This guide outlines the process of setting up browser push notifications for a Node.js web application, using an Express server and the node-pushnotifications library to manage web push notifications. The setup involves creating a server to handle subscription requests, a client-side script to send these requests, and a service worker to manage and display notifications in the browser. The guide emphasizes the importance of security considerations, such as setting appropriate CORS policies and properly managing VAPID keys, especially in production environments. Additionally, it touches on the need for cross-channel communication and suggests using platforms like Knock for handling complex notification workflows across different channels.