Simple question...

I have seen people tell me to use "\r\n" in various places and others tell me to use "\n" in the same place. I'm sure one is right and one is wrong. Example - when designing mail() headers:

Tutorial #1:

```
//define the headers we want passed. Note that they are separated with \r\n 
$headers = "From: webmaster@example.com\r\nReply-To: webmaster@example.com"; 
//add boundary string and mime type specification 
$headers .= "\r\nContent-Type: multipart/mixed; boundary=\"PHP-mixed-".$random_hash."\""; 

```

Tutorial #2 (notice the header argument):

```
mail($to, $subject, $body, 
    "From: " . $from . "\n" . 
    "bcc: " . $bcc . "\n" . 
    "MIME-Version: 1.0\n" . 
    "Content-Type: multipart/alternative;\n" . 
    "     boundary=" . $mime_boundary_header)

```

I am confused, but clearly it makes somewhat of a difference, because with one, my headers worked, and with the other they only **sometimes** work.