<center><h1>Replacing text</h1></center>
<div id=ReplaceMe>
What you type in below will replace this text. 
If you type nothing in the box, but simply click the button, you will delete the text.</div>
<br>
<form>
<input id=T1 type=text style="width: 400"><p>
<input type=button value="Click me to Change" onclick="ReplaceMe.innerHTML = T1.value"></p>
</form>