JS: Display tooltip over page element

To display a tooltip over a page element:

1. Create hidden tooltip element:
   

   
      Some tooltip info
   

2. Create JS scripts for showing/hiding tooltip:
   

   function show()
   {
   var tooltip = document.getElementById('tooltip');
   tooltip.style.top = event.clientY;
   tooltip.style.left = event.clientX + 10;
   tooltip.style.display = 'block';
   }
   
   function hide(){
   var tooltip = document.getElementById('tooltip');
   tooltip.style.display = 'none';
   }

3. Set Javascript events for the chosen page element:
   

   
      Element content
   

Tested on IE7.