JavaScript Slider Photo

<script type="text/javascript">

//store the image into an array

var Imgarr=["picName.jpg","picName.png","picName.png"];

var index=0;

function slider() {

index++;

if (index==Imgarr.length)

{

index=0;

document.getElementById("im1").src="FolderNameimg/"+Imgarr[index];

}

else

{

document.getElementById("im1").src="FolderNameimg/"+Imgarr[index];

}

setTimeout("slider()",1000);

}

</script>

<div id="slider"><img id="im1" src="FolderNameimg/angad (17).jpg" height="300px" width="1000px"/>

</div>