Building a secure chat application requires encryption to protect users' communication. End-to-end encryption ensures that only the sender and receiver can see the messages, and it's crucial for maintaining privacy. Popular technologies like Firebase, websockets (with Socket.IO), and chat messaging APIs/SDKs can be used to develop such an app. This tutorial'll focus on using Socket.IO with Node.js and Express. The front end handles message input, display, and sending via a socket connection. The backend accepts socket connections, processes data, and stores it in a database. Notifications and handling of disconnections are essential aspects to consider for a seamless experience. Click here to know more