Lecture 390:- Introduction - Server Side Events

Server-Sent Events (SSE) is a technology that allows a server to push data to a client once a client establishes a persistent connection with the server over the HTTP or HTTPS protocol. Unlike WebSockets, SSEs are unidirectional, which means data is pushed only from the server to the client, and not vice versa. SSEs are an alternative to long polling, which involves sending an HTTP request to the server and keeping the connection open until the server responds with new data.

SSEs are used in many web applications, such as real-time notifications, chat applications, stock market tickers, and many more. They offer several advantages over traditional AJAX polling:

1. Real-time updates: SSEs allow the server to push data to the client as soon as it becomes available, without waiting for the client to request it.
2. Reduced network traffic: SSEs use a single, persistent connection, reducing the number of HTTP requests required to update the page.
3. Improved performance: SSEs reduce the latency and overhead associated with polling, resulting in improved performance and reduced server load.

Overall, SSEs provide an efficient and reliable way to send real-time updates from the server to the client.