From: sender@example.com To: recipient@example.com Subject: Multipart Email Example Content-Type: multipart/alternative; boundary="boundary-string" --boundary-string Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Plain text email goes here! This is the fallback if email client does not support HTML --boundary-string Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline <h1>This is the HTML Section!</h1> <p>This is what displays in most modern email clients</p> --boundary-string--