Functions

<script language="javascript1.1">
function mungeName(person)
{
  return person + "aroo"
}
</script>

<form name="sample">
<input type="text" name="person" value="">
<input type="button" 
       name="clickme" 
       value="Click Me"
       onClick="document.sample.person.value=mungeName(document.sample.person.value)">
</form>