No section text, so add your own here.. - wikipedia 
# Content-Type
This header indicates the media type of the message content, consisting of a ''type'' and ''subtype'', for example - wikipedia
Content-Type: text/plain
Through the use of the ''multipart'' type, MIME allows mail messages to have parts arranged in a tree structure where the leaf nodes are any non-multipart content type and the non-leaf nodes are any of a variety of multipart types.
# Content-Transfer-Encoding
In June 1992, MIME (RFC 1341, since made obsolete by RFC 2045) defined a set of methods for representing binary data in formats other than ASCII text format. The ''content-transfer-encoding:'' MIME header has 2-sided significance: - wikipedia
# Content-Disposition
The original MIME specifications only described the structure of mail messages. They did not address the issue of presentation styles. The content-disposition header field was added in RFC 2183 to specify the presentation style. A MIME part can have: - wikipedia
# MIME-Version
The presence of this header indicates the message is MIME-formatted. The value is typically "1.0" so this header appears as - wikipedia
MIME-Version: 1.0
# History of MIME
According to MIME co-creator Nathaniel Borenstein, the intention was to allow MIME to change, to advance to version 2.0 and so forth, but this decision led to the opposite outcome, making it nearly impossible to create a new version of the standard.
We did not adequately specify how to handle a future MIME version... So if you write something that knows 1.0, what should you do if you encounter 2.0 or 1.1? I sort of thought it was obvious but it turned out everyone implemented that in different ways. And the result is that it would be just about impossible for the Internet to ever define a 2.0 or a 1.1.
# See also