W3Schools Tryit Editor

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
<style>
canvas {
    border:1px solid #d3d3d3;
    background-color: #f1f1f1;
}
</style>
</head>
<body onload="startGame()">
<script>

var myGamePiece;

function startGame() {
    myGamePiece = new component(30, 30, "smiley.gif", 10, 120, "image");
    myGameArea.start();
}

function updateGameArea() {
    myGameArea.clear();
    myGamePiece.newPos();
    myGamePiece.update();
}

function clearmove() {
    myGamePiece.image.src = "smiley.gif";
    myGamePiece.speedX = 0; 
    myGamePiece.speedY = 0; 
}
</script>
<div style="text-align:center;width:480px;">
  <button onmousedown="move('up')" onmouseup="clearmove()" ontouchstart="move('up')">UP</button><br><br>
  <button onmousedown="move('left')" onmouseup="clearmove()" ontouchstart="move('left')">LEFT</button>
  <button onmousedown="move('right')" onmouseup="clearmove()" ontouchstart="move('right')">RIGHT</button><br><br>
  <button onmousedown="move('down')" onmouseup="clearmove()" ontouchstart="move('down')">DOWN</button>
</div>

<p>See the image changes when you click on a button.</p>
</body>

</html>

​x
 
<!DOCTYPE html><html><head><meta name="viewport" content="width=device-width, initial-scale=1.0"/><style>canvas {    border:1px solid #d3d3d3;    background-color: #f1f1f1;}</style></head><body onload="startGame()"><script>​var myGamePiece;​function startGame() {    myGamePiece = new component(30, 30, "smiley.gif", 10, 120, "image");    myGameArea.start();}​var myGameArea = {    canvas : document.createElement("canvas"),    start : function() {        this.canvas.width = 480;        this.canvas.height = 270;        this.context = this.canvas.getContext("2d");        document.body.insertBefore(this.canvas, document.body.childNodes[0]);        this.frameNo = 0;        this.interval = setInterval(updateGameArea, 20);        },    clear : function() {        this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);    },    stop : function() {        clearInterval(this.interval);    }}​function component(width, height, color, x, y, type) {    this.type = type;    if (type == "image") {        this.image = new Image();        this.image.src = color;    }