message/*

24 registered types — the explained ones link through.

/
  • message/bhttpregistered
  • message/cpimregistered
  • message/delivery-statusregistered
  • message/disposition-notificationregistered
  • message/external-bodyregistered
  • message/feedback-reportregistered
  • message/globalregistered
  • message/global-delivery-statusregistered
  • message/global-disposition-notificationregistered
  • message/global-headersregistered
  • message/httpregistered
  • message/imdn+xmlregistered
  • message/mlsregistered
  • message/newsde facto
  • message/ohttp-reqregistered
  • message/ohttp-resregistered
  • message/partialregistered
  • message/rfc822registered
  • message/s-httpde facto
  • message/sipregistered
  • message/sipfragregistered
  • message/tracking-statusregistered
  • message/vnd.si.simpde facto
  • message/vnd.wfa.wscregistered

"Registered" rows are in the IANA registry; "de facto" types circulate unregistered. Registry mirror: mime-db (MIT).