When i scan the WhatsApp code on my phone, the web site switches IMMEDIATELY to the actual WhatsApp page with the chats and all. I was wondering, how does the whole process look like? When I scan, my mobile probably recognized the code that's stored on the server and sends an Ajax request, but then how does the browser realize that the server received the request? is there some kind of "reverse Ajax" request from server to client? It happens so fast it's astonishing, and I really want to know what's up (heyoo sorry for the pun).
I did not check their code but it must be WebSockets.