title: Websocket: are server data sent synchronously?
body: <p>I'm using nodejs + websocket module to establish a connection between the client and the server through a websocket. 
  The server emits several times data to the client: I know it's a TCP connection, but let me delete every doubt about it. 
  Are the "emits" sequential? If the first "emit" was done at time 1s and the second "emit" at time 2s, will the client receive for sure the first emit and then the second one?
  What happens if the first emit is not received yet and the second one is emitted?
  Are emits blocking calls?</p>