[Dilettante_Pro]

Появляются

<style>
canvas {
    width:300px;
    height:150px;
    border:1px solid black;
}
</style>
<canvas id="canvas"></canvas>
<script>
  var canvas = document.getElementById('canvas');
     var ctx = canvas.getContext('2d');
    canvas.addEventListener("click", function() {
       ctx.beginPath();
       ctx.arc(75,75,50,0,Math.PI*2,true);
       ctx.stroke();
    });
</script>