function random_img(){
  var myimages=new Array()
  //specify random images below. You can have as many as you wish
  myimages[1]="imgs/banner1.jpg"
  myimages[2]="imgs/banner2.jpg"
  myimages[3]="imgs/banner3.jpg"
  myimages[4]="imgs/banner4.jpg"
  myimages[5]="imgs/banner5.jpg"
  
  

  var ry=Math.floor(Math.random()*myimages.length)

  if (ry==0)
     ry=1
     document.write('<img src="'+myimages[ry]+'" + alt="Ro Ceramics" width=760px height=200px> ')
}
 random_img()