<canvas id="canvas"></canvas>
<script>
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
ctx.beginPath();
ctx.rect(x, y, width, height);
ctx.fillStyle = 'limegreen';
ctx.fill();
ctx.beginPath();
ctx.arc(x, y, radius, startAngle, endAngle, counterClockWise(optional));
ctx.strokeStyle = 'black';
ctx.stroke();
</script>//Creates a canvas and draws a circle
var canvas = document.body.appendChild(document.createElement("canvas"));
var ctx = canvas.getContext("2d");
ctx.beginPath();
ctx.arc(canvas.width / 2, canvas.height / 2, 50, 0, Math.PI * 2);
ctx.fillStyle = "red";
ctx.strokeStyle = "black";
ctx.stroke();
ctx.fill();#this code creates a circle within a canvas that must be created in HTML
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.beginPath();
ctx.arc(95, 50, 40, 0, 2 * Math.PI);
ctx.stroke();<!DOCTYPE HTML>
<html>
<head>
<style>
#mycanvas{border:1px solid red;}
</style>
</head>
<body>
<canvas id = "mycanvas" width = "100" height = "100"></canvas>
</body>
</html><canvas id="" width="" height=""></canvas>
<script>
</script>