http://www.rfc-editor.org/rfc/rfc2388.txt
RFC 2388: Returning Values from Forms: multipart/form-data, L. Masinter1998-08-01T23:00:00-00:00This specification defines an Internet Media Type, multipart/form-data, which can be used by a wide variety of applications and transported by a wide variety of protocols as a way of returning a set of values as the result of a user filling out a form. [STANDARDS-TRACK]