<canvas
   id="Canvasobject3"
width="200"
height="200"
style="border: 2px solid #0000FF;">Ihr Browser unterstützt leider nicht das HTML5-Canvas-Element.
</canvas>

<script type="text/javascript">
var c = document.getElementById("Canvasobject3");
var cxt = c.getContext("2d");
cxt.fillStyle ="#FF0000";
cxt.beginPath();
cxt.arc(50,18,15,0,Math.PI*2,true);
cxt.closePath();
cxt.fill();
</script>