RFC 2278:IANA Charset Regi...
RFC-Ref

1. Abstract

   MIME [RFC-2045, RFC-2046, RFC-2047, RFC-2184] and various other
   modern Internet protocols are capable of using many different
   charsets. This in turn means that the ability to label different
   charsets is essential. This registration procedure exists solely to
   associate a specific name or names with a given charset and to give
   an indication of whether or not a given charset can be used in MIME
   text objects. In particular, the general applicability and
   appropriateness of a given registered charset is a protocol issue,
   not a registration issue, and is not dealt with by this registration
   procedure.

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