socket.io chat

<!DOCTYPE html>
<html>
  <head>
    <title>Chat Application Using Socket.IO</title>
  </head>
  <body>
    <input type="text" id="userName" placeholder="User name" /><br>
    <textarea id="chatBody" placeholder="Body..." style="width: 500px;" rows="6"></textarea><br>
    <button id="sendMessage">Send</button>
    <div id="chat">

    </div>

    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
    <script src="/socket.io/socket.io.js"></script>

    <script>
      $(document).ready(function(){
        var socket = io('http://localhost');
        $("#sendMessage").click(function(){
          $name = $("#userName").val();
          $body = $("#chatBody").val();
          socket.emit("sendMessage", {
            name: $name,
            body: $body
          });
        });

        socket.on("displayMessage", function(data){
            $name = data.name, $body = data.chatBody;
            $message = "<div><h4>"+$name+"</h4><br><pre>"+$body+"</pre></div>";
            $("#chat").prepend($message);
          });
        });
    </script>
  </body>
</html>