<script language="javascript">
function toggle() {
	var ele = document.getElementById("toggleText");
	var text = document.getElementById("displayText");
	if(ele.style.display == "block") {
    		ele.style.display = "none";
		text.innerHTML = "show";
  	}
	else {
		ele.style.display = "block";
		text.innerHTML = "hide";
	}
}
</script>
<a id="displayText" href="javascript:toggle();">show</a> <== click Here
<div id="toggleText" style="display: none"><h1>peek-a-boo</h1></div>

another option would be

<script language='javascript'>
			function showme() {
			var ele = document.getElementById('hideme');
	   		ele.style.visibility = 'visible';

			}
			function hideme() {
			var ele = document.getElementById('hideme');
	   		ele.style.visibility = 'hidden';

			} 

</script>