memasukkan nama

<script type="text/javascript">
<!--
function displayMessage(firstName) {
    alert("Hello " + firstName + ", hope you like JavaScript functions!")
}
//-->
</script>
<form>
First name:
<input type="input" name="yourName" />
<input
  type="button"
  onclick="displayMessage(form.yourName.value)"
  value="Display Message" />
</form>

hasilnya

First name: