Cookies expire time frame

I see in the code there’s

function wpfp_set_cookie($post_id, $str) {
    $expire = time()+60*60*24*30;
    return setcookie("wp-favorite-posts[$post_id]", $str, $expire, "/");
}

sounds like thats for making the cookies expire after a certain time right? whats the set time?

http://wordpress.org/extend/plugins/wp-favorite-posts/