What is the correct syntax for adding a Bcc recipient in the mail() function in PHP?

When using the mail() function in PHP to send an email, you can include Bcc recipients by adding an additional header parameter in the mail() function. The correct syntax for adding a Bcc recipient is to include "Bcc: email@example.com" as a header parameter in the mail() function. This allows you to send a blind carbon copy of the email to the specified recipient without other recipients being aware of it.

$to = "recipient@example.com";
$subject = "Subject";
$message = "This is a test email.";
$headers = "From: sender@example.com\r\n";
$headers .= "Bcc: email@example.com\r\n";

mail($to, $subject, $message, $headers);