MIME

MultipurposeInternetMailExtensions

MIME extends the format of Internet EMail to allow non-US-ASCII textual messages, non-textual messages, multipart message bodies, and non-US-ASCII information in message headers. http://www.mhonarc.org/~ehood/MIME/

http://www.iana.org/assignments/media-types/

XHTML http://www.xml.com/pub/a/2003/03/19/dive-into-xml.html |issues