// source http://jsbin.com/codeluj

index.html

<h1 id = "h1Id">Title</h1>
<p id = "pId">Paragraph</p>
<input id = "inputId">
<button onclick="aButton()">Button</button>
<script id="jsbin-javascript">
//alert("pop");
function aButton(){
  var clickAButton = document.getElementById("inputId").value;
  document.getElementById("pId").innerHTML = clickAButton;
}
</script>


<script id="jsbin-source-javascript" type="text/javascript">//alert("pop");
function aButton(){
  var clickAButton = document.getElementById("inputId").value;
  document.getElementById("pId").innerHTML = clickAButton;
}</script>

jsbin.codeluj.js

//alert("pop");
function aButton(){
  var clickAButton = document.getElementById("inputId").value;
  document.getElementById("pId").innerHTML = clickAButton;
}