// <script language="javascript">
pics = new Array();
var objCount = 0; // quantity of pictures on the web-page

function preload(name, first, second) {

  // pictures preload and placement it into array

    pics[objCount] = new Array(3);
    pics[objCount][0] = new Image();
    pics[objCount][0].src = first;
    pics[objCount][1] = new Image();
    pics[objCount][1].src = second;
    pics[objCount][2] = name;
    objCount++;

}

function on(name){

     for (i = 0; i < objCount; i++) {
      if (document.images[pics[i][2]] != null)
        if (name != pics[i][2]) {
  // all others pictures back to initial state
            document.images[pics[i][2]].src = pics[i][0].src;
        } else {
 // show second pictures, because cursor on current pictures 
              document.images[pics[i][2]].src = pics[i][1].src;
        }
    }

}

function off(){

     for (i = 0; i < objCount; i++) {
      // all pictures back to initial state
      if (document.images[pics[i][2]] != null)
            document.images[pics[i][2]].src = pics[i][0].src;
    }

}


preload('contents', './images/contents1.gif', './images/contents2.gif');
preload('about', './images/about1.gif', './images/about2.gif');
preload('com8', './images/com8_1.gif', './images/com8_2.gif');
// </script>