<a class="buton1" href="#">fadeIn</a>
<a class="buton2" href="#">fadeOut</a>
<span>W3TR</span>

a{display: inline-block; background: #00FF99; padding:20px; border-bottom:4px solid #00CC00; color:#00CC99; text-decoration:none; margin-bottom:20px;}
span{display:block; font-size:30px; color:red; margin-bottom:20px;}

$(".buton1").click(function(){
  $("span").fadeOut()
});
$(".buton2").click(function(){
  $("span").fadeIn();
});