title: how to build multi-user video chatting web app using webRTC, node.js and socket.io
body: <p>im trying to make a web app that supports multi-user video chatting. ive read an article about webrtc on "getting started with webrtc" 
  (<a href="http://www.html5rocks.com/en/tutorials/webrtc/basics/" rel="noreferrer">http://www.html5rocks.com/en/tutorials/webrtc/basics/</a>) and done some demo on codelab. but i still dont really know how to make it a 3-way conferencing call.i dont really know a lot about node.js and socket.io. just started learning them because im trying to build this video web app.</p>
  
  <p>so my question is which part of webrtc or socket.io determines that more than 2 users can join the call? or any resource that you guys get direct me to?</p>
  
  <p>thanks in advance. </p>