In what situations might the use of parameters like "-f" be necessary when sending emails through PHP scripts?

When sending emails through PHP scripts, using parameters like "-f" can be necessary when specifying the "From" address in the email headers. This is important for ensuring that the email is not marked as spam by the recipient's email server. By using the "-f" parameter, you can set the envelope sender address, which should match the "From" address in the email headers.

$to = "recipient@example.com";
$subject = "Test Email";
$message = "This is a test email.";
$headers = "From: sender@example.com";
$additional_parameters = "-f sender@example.com";

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