Reasons to use AngularJS: Without Angular

bindingWithoutAngular.html

<input type="text" id="messageInput"/>
<span id="messageOutput"></span>
<script type="text/javascript">
(function () {
  var input = document.getElementById('messageInput');
  var output = document.getElementById('messageOutput');
  input.addEventListener('change', function () {
    output.innerHTML = input.value;
  });
})();
</script>