Multipurpose Internet Mail Extensions (MIME) is an Internet Standard for the format of e-mail. Virtually all human-written Internet e-mail and a fairly large proportion of automated e-mail is transmitted via SMTP in MIME format. Internet e-mail is so closely associated with the SMTP and MIME standards that it is sometimes called SMTP/MIME e-mail.
MIME is specified in five parts starting with RFC 2045, RFC 2046, and RFC 2047.
Introduction
The basic Internet e-mail transmission protocol, SMTP, supports only 7-bit ASCII characters (see also 8BITMIME).
This effectively limits Internet e-mail to messages which, when transmitted, include only the characters sufficient for writing a small number of languages, primarily English. Other languages based on the Latin alphabet typically include diacritics not supported in 7-bit ASCII, meaning text in these languages cannot be correctly represented in basic e-mail.
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