Common Internet Message Header Fields

摘要

This memo contains tables of commonly occurring headerfields in headings of e-mail messages. The documentcompiles information from other RFCs such as RFC 822, RFC1036, RFC 1123, RFC 2156, RFC 1496, RFC 1766, RFC 2183, RFC1864, RFC 2421 and RFC 2045. A few commonly occurringheader fields which are not defined in RFCs are alsoincluded. For each header field, the memo gives a shortdescription and a reference to the RFC in which the headerfield is defined.The latest, revised version of this document can be foundat URLhttp://www.dsv.su.se/jpalme/ietf/mail-headers/.The version at that URL may be more recent than the versionpublished as an RFC.