Untitled

<html>
  <head>
    <title>Pong!</title>
    <script>

var run = function() {
  var canvas = document.getElementById("game");
  var ctx = canvas.getContext("2d");
  ctx.fillStyle = "red";
  ctx.fillRect(0, 0, 150, 75);

  ctx.fillStyle = "black";
  ctx.fillText("Mr. K was here", 10, 20);

};

var keypress = function(e) {
    if (e.keyCode == 38 || e.keyCode == 40) {
        alert(e.keyCode);
    }
};

setInterval(run, 20);

window.addEventListener("keydown",keypress,false);

    </script>
  </head>
  <body onload="run()">

    <canvas id=game width=600 height=400></canvas>

  </body>
</html>