What are the advantages of using a library like PHPMailer or Symfony Mailer over the mail() function for sending emails?

Using a library like PHPMailer or Symfony Mailer over the mail() function offers several advantages, such as better security features, easier handling of attachments and HTML emails, built-in support for SMTP authentication, and better error handling capabilities. These libraries provide a more robust and reliable way to send emails compared to the basic functionality provided by the mail() function.

// Example using PHPMailer library
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\SMTP;
use PHPMailer\PHPMailer\Exception;

// Load Composer's autoloader
require 'vendor/autoload.php';

// Instantiation and passing `true` enables exceptions
$mail = new PHPMailer(true);

try {
    //Server settings
    $mail->isSMTP();
    $mail->Host = 'smtp.example.com';
    $mail->SMTPAuth = true;
    $mail->Username = 'user@example.com';
    $mail->Password = 'secret';
    $mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
    $mail->Port = 587;

    //Recipients
    $mail->setFrom('from@example.com', 'Your Name');
    $mail->addAddress('recipient@example.net', 'Recipient Name');

    //Content
    $mail->isHTML(true);
    $mail->Subject = 'Subject';
    $mail->Body    = 'This is the HTML message body <b>in bold!</b>';

    $mail->send();
    echo 'Message has been sent';
} catch (Exception $e) {
    echo "Message could not be sent. Mailer Error: {$mail->ErrorInfo}";
}