jQuery, ".slideToggle"
  
  
  
  
   this is <div id="slideDiv">
    
    Put this code in the <head>of your html:
    
  <script src="jquery-1.7.1.min.js" type="text/javascript" charset="utf-8"></script>
  
    Save this code as 
  "jquery-1.7.1.min.js", and put it in the same directory as your html page:
  
  jquery-1.7.1.min.js
  
  
   
  
  
  
     this is <div id="slideDiv2">
    
    
    Put this code in the <head>of your html:
    <script type="text/javascript">
    $(document).ready(function(){
    $("#slideDiv").hide();
    $("#slideDiv2").hide();
  
    $(window).load(function(){
  
    $("#toggle").click(function(){
    $("#slideDiv").slideToggle(500);
    });
    $("#toggle2").click(function(){
    $("#slideDiv2").slideToggle(500);
    });
  
    }); 
    });
  </script> 
  
  
Examples:
fractalcatmusic.com
fractalcat.bandcamp.com