window.onload = choosePic;

var myPix = new Array("images/tile-01.jpg","images/tile-02.jpg","images/tile-03.jpg","images/tile-04.jpg","images/tile-05.jpg","images/tile-06.jpg");

function choosePic() {
	randomNum = Math.floor((Math.random() * myPix.length));
	document.getElementById("myTile").src = myPix[randomNum];
}