in web applications, some cases we want to send some data from server side to client side (web browser) needn't the client send request. ButI can't know how to do?.
Example, I develop a web based chat application. in that, I have 2 persons A, B. A send data to B via server side, and then server side send the data to A. Assume that, A connected Server side before.
P/S: By the way, could you show me ideas to build a web based chat instead of.
Thank you so much !