Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<head>
<script>
function lighton() {
    document.getElementById('myimage').src = "bulbon.gif";
}
function lightoff() {
    document.getElementById('myimage').src = "bulboff.gif";
}
</script>
</head>

<body>

<img id="myimage" onmousedown="lighton()" onmouseup="lightoff()" src="bulboff.gif" width="100" height="180" />

<p>Click mouse and hold down!</p>

</body>
</html>