eror fungsi mail di php gan

Permisi, gan ane udah masuk tutrial ngirim email php dari bang hilman, tapi dapat eror ginian.

Warning: mail(): Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set() in C:\xampp\htdocs\lrn_email\index.php on line 14
email gagal dikirim

ini kode saya.

<?php

if (isset ($_POST['submit'])){

    $email = $_POST['email'];
    $subject = $_POST['subject'];
    $pesan = $_POST['pesan'];


    if(mail($email, $subject, $pesan)){
        echo "email berhasil dikirim";
    }else {
        echo "email gagal dikirim";
    }
}

?>

<form action="index.php" method="post">

<input type="text" name="email" placeholder="kirim ke-"> <br>
<input type="text" name="subject" placeholder="Masukkan Judul Pesan Anda"><br>
<textarea name="pesan" placeholder="Masukkan isi pesan anda" id="" cols="30" rows="10"></textarea><br>

<input type="submit" name="submit" value="kirim">

</form>

mohon bantuannya gan.