title: What is the difference between io.sockets.emit and socket.emit in io.on('connection', function(socket){})?
body: <p>I noticed if I want to emit a message like</p>
  
  <pre><code>io.on('connection', function(socket){
      socket.emit('signal')
  })
  </code></pre>
  
  <p>Somehow I have to refresh the HTML page to get the ejs file work on the signal. But If I directly emit it like:</p>
  
  <pre><code>io.sockets.emit('signal')
  </code></pre>
  
  <p>Then I do not have to refresh the html to get the action work.</p>
  
  <p>How come?</p>