hi i'm working on an ajax response but i'm just confuse on how will i get the return data of the response.

here's the code


Code:
$(document).ready(function () {

    $('#submit').click(function () {
           function access(postcodes,submits){
                $.ajax({
                    type: "POST",
                    url: "index.php",
                    data: { 'submit':submits, 'postcode': postcodes },
                    success: function (data,status) {
                        reuturn 
                    }
                });
           }

           var submits = $('#submit').val();
           var postcodes = $('#postcode').val();
           access(postcodes, submits);
	
    });



});
<script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>

<script src="ajax.js"></script>

<form method="POST" action="">
insert postcode:<input type="text" id="postcode" name="postcode">
<input type="button" id="submit" name="submit" value="submit">
</form>


PHP Code:
<?php
if($_POST['submit']=="submit"){
    if(
$_post['postcode']){
echo 
"this is the value";
}

}
?>
what do i need to do to get the return??