MIME Overview

Multipurpose Internet Mail Extensions (MIME) is a communications standard that enables the transfer of non-ASCII formats over protocols, such as SMTP, that only support 7-bit ASCII characters.

Examples of non-ASCII formats, include:

MIME defines different ways of encoding the non-ASCII formats so that they can be represented using characters in the 7-bit ASCII character set.

MIME also defines additional email headers that contain information about:

The resulting MIME message can be "decoded" or "re-encoded" after transmission. We say "re-encoded", because the MIME messages can be converted into a different character set from the original message.

The following sections describe some of the key concepts of MIME messages.