Sending Email PHP

I have the following code:

$para      = $_REQUEST['EMAIL'];
$titulo    = 'El título probando';
$mensaje   = 'es de prueba';
$cabeceras = 'From: Equipo blabla' . "\r\n" .
'Reply-To: ese' . "\r\n" .
'X-Mailer: PHP/' . phpversion();

mail($para, $titulo, $mensaje, $cabeceras);

And I have the following error:

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\ProyectoLuifer01\Controller.php on line 30

I went to the php.ini and I have:

SMTP=localhost
smtp_port=25
mail.add_x_header=On

I'm trying, I'm not with any server and that of SMTP and protocols I do not understand much ...