var theImages = new Array()

theImages[0] = 'http://www.chizeng.com/webclub/images/indeximages/indeximage1.jpg'
theImages[1] = 'http://www.chizeng.com/webclub/images/indeximages/indeximage2.jpg'
theImages[2] = 'http://www.chizeng.com/webclub/images/indeximages/indeximage3.jpg'
theImages[3] = 'http://www.chizeng.com/webclub/images/indeximages/indeximage4.jpg'

var j = 0
var p = theImages.length;

var preBuffer = new Array()
for (i = 0; i < p; i++){
   preBuffer[i] = new Image()
   preBuffer[i].src = theImages[i]
}

var whichImage = Math.round(Math.random()*(p-1));
function showImage(){
document.write('<img src="'+theImages[whichImage]+'" class="indeximage" alt="CHS Web Design Club">');
}