title: How node's live server Works?
body: <p>I was using the node's live server by installing it by NPM.
  if I am changing something in my files its refreshing my browser. I was searching on the Internet but not able to find it.</p>
  
  <p>I want to know how this NPM package works?
  When I hit the CTRL + S for saving in my local file how the browser gets the refreshing hit. 
  Does something like socket.io working at backend or something else?</p>