Regardless of official terminology, there are two levels:
1. Map a character to a unique number in a character set (in Unicode: called codepoint)
2. Map a number that represents a character in a character set to a bit pattern for storage (transiently or persistently, internally or externally). Unicode code points can be bit-encoded in various ways: UTF8, UCS2 and UCS4/UTF32.
The original code points permit the same character to be represented in various ways, which makes equality checks non-trivial: for instance a character like "ä" can be represented as a single character or alternatively as a composition of "a" + umlaut accent (2 characters).
So far, this is all about plain text, so we are not talking about font families or character properties (bold, italics, underlined) or orientation (super-script, sup-script).
1. Map a character to a unique number in a character set (in Unicode: called codepoint)
2. Map a number that represents a character in a character set to a bit pattern for storage (transiently or persistently, internally or externally). Unicode code points can be bit-encoded in various ways: UTF8, UCS2 and UCS4/UTF32.
The original code points permit the same character to be represented in various ways, which makes equality checks non-trivial: for instance a character like "ä" can be represented as a single character or alternatively as a composition of "a" + umlaut accent (2 characters).
So far, this is all about plain text, so we are not talking about font families or character properties (bold, italics, underlined) or orientation (super-script, sup-script).
Ken Lunde's opus magnum is the standard book on representing text in various languages other than English, with a focus on Asian languages: https://www.oreilly.com/library/view/cjkv-information-proces...