009.010

Message Mechanics (MIME, Attachments, List-Unsub)

The "nuts and bolts" of a raw email. This section covers the technical structure of a message, including the MIME format, how attachments are Base64 encoded, and the technical implementation of the header (RFC 2369).

9 questions in this topic

What is MIME (Multipurpose Internet Mail Extensions)? What are MIME types? How are HTML and plain text emails structured using MIME? How do attachments work in email? Do attachments affect deliverability? What file types are risky to send as attachments? What is the List-Unsubscribe header? What's the difference between mailto: and http: List-Unsubscribe? What are Precedence: bulk and Auto-Submitted headers?