<!-- Hide this script from old browsers --
var random = Math.random() ;
var picnum = Math.round(random*5)+1;
//You can change the number of images by changing the number in the line that reads, 
//"var picnum = Math.round(random*4)+1". Be sure to make the number (currently 4) one less than the number of images you put in the directory. 
// -- End Hiding Here -->// JavaScript Document