How to send emails on Drupal in PHP code??

$from_site = variable_get(‘site_mail’, ini_get(‘sendmail_from’)); // fetch site-email address.

if ($from_site) {
$headers[‘Sender’] = $headers[‘Return-Path’] = $headers[‘Errors-To’] = $from_site;
}

 

if (!($success = drupal_mail(‘invite-mail’, $toemail , $subject, wordwrap($body, 72), $from_site, $headers))) {
static $error_shown = FALSE;
if (!$error_shown) {
drupal_set_message(t(‘Problems occurred while sending the invitation(s). Please contact the site administrator.’), ‘error’);
$error_shown = TRUE;
}

}

css.php