Listing 8: Structure for HTML Message 
Normal Headers
Content-Type: multipart/alternative;

boundary="some_unique_string_not_in_email"

--some_unique_string_not_in_email
Content-Type: text/plain; charset=us-ascii


Text email message here.

--some_unique_string_not_in_email
Content-Type: text/html; charset=us-ascii


<html>
<head>
<title>some subject</title>
</head>
<body>

Your <b>Html</b> email message here.
    </body>
</html>

--some_unique_string_not_in_email--