$fromEmail = "admin@domain.com"; 
$subject = "Welcome";
$body = "Hi,\n\nYou have visited the page.";
if (mail($Email, $subject, $body, "From: $fromEmail")) {
  echo("<p>Message successfully sent!</p>");
 } else {
  echo("<p>Message delivery failed...</p>");
 }

<?php
$to      = 'nobody@example.com';
$subject = 'the subject';
$message = 'hello';
$headers = 'From: webmaster@example.com' . "\r\n" .
    'Reply-To: webmaster@example.com' . "\r\n" .
    'X-Mailer: PHP/' . phpversion();
 
$check = mail($to, $subject, $message, $headers);
if($check)
{
echo "mail sent successfully. ";
}
else
{
echo "Faid to sent. ";
} 
?>

include("Mail.php");
 
$from = "Admin <admin@domain.com>";
$to = "user <user@domain.com>";
$subject = "Hi!";
$body = "Hi,\n\nHow are you?";
 
$host = "exchange.domain.com";
$username = "admin";
$password = "adminpassword";
 
$headers = array ('From' => $from,'To' => $to,'Subject' => $subject);
$smtp = Mail::factory('smtp',array ('host' => $host,'auth' => true,'username' => $username,'password' => $password));
 
$mail = $smtp->send($to, $headers, $body);
 
if (PEAR::isError($mail)) {
echo("<p>" . $mail->getMessage() . "</p>");
} else {
echo("<p>Message successfully sent!</p>");
}