What is the PreSaveAction

We have added a PreSaveAction JavaScript function to the page.

Return a True or False to allow the save to continue.
Example:

<script type="text/javascript">
 function PreSaveAction() {
  // pre save action alert message
  alert('form has been submitted!');
  return true;  // return true to continue with the save 
       // return false;          // or return false to cancel the save
 } 
</script>