path = "../../img/";		//from the perspective of the html file
banner = new Array("main-banner-chimney.jpg","main-banner-dicussion.jpg","main-banner-tree.jpg","main-banner-dolphin.jpg");
dice = Math.round(Math.random()*banner.length);
if(dice>=banner.length){dice--};
document.write("<img src="+path+banner[dice]+">");