Code:
<?php


if (isset($_POST['submit'])) {
    $fromEmail = $POST['fromEmail'];
    $body = $_POST['body'];
    mail('[email protected]','Message from web site', $body, 'From: ' . $fromEmail . "\n\r");
    echo 'Thank you for contacting us.';
} else {
    die('Why are you here ? Want to hack my Script ?');
}