Script to change the div text on button click
<script type="text/javascript">
function replaceText()
{
document.getElementById("divid").innerHTML = "replaced text."
}
</script>
the div
<div id="divid">original text</div>
the button to change the div's content
<input type="button" onclick="replaceText()" value="Click me to change the content" />
Or are you looking at something like Ajax that would render the content from a web request?