Aşağıdaki kodu ... çizgisinin altındaki kodları anlamada bana yardım ...

if (isset($_POST['register'])) {
    $error = array();

    if (!in_array(strtolower($_POST['captcha']), $aCaptcha[$_SESSION['captcha']])) {
        $error['captcha'] = "<span style='color:red'>The name of the animal is not correct.</span>";
    }
    if (count($error) == 0) {
        //no errors, do other actions here, like saving into database, send email or...
        echo "<span style='color:red'>Thank you for completing the form.
We shall contact you soon.</span>";
        die();