The Multipurpose Internet Mail Extensions (MIME) introduces Internet Media Types, including text representations besides ASCII. The Hypertext Markup Language (HTML) used in the World-Wide Web is a proposed Internet Media Type. But HTML is also an application of Standard Generalized Markup Language (SGML).
In the MIME and SGML specifications, the discussion of characters representation is notoriously complex, and apparently subtly inconsistent or incompatible. This document presents a collection of terms intended to reconcile the two specifications and serve as a basis for rigorous discussion of characters and their digital representations.