Or maybe you meant to say: A single abstract character (or code point) can be made up of multiple code units.
Unfortunately, the term “character“ alone is ambiguous because depending on the context it can refer to either code points or code units.
Unfortunately, the term “character“ alone is ambiguous because depending on the context it can refer to either code points or code units.
A code point is the atomic unit of the abstract Unicode encoding. By "abstract" I mean it is not an actual text encoding you can write to a file.
A code unit is the atomic unit of an actual text encoding, such as UTF-8, UTF-16LE or UTF-32LE (and their BE equivalents).
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So to put it together a "user-perceived character" is made up of one or more "code points". When implemented in an application, each "code point" is encoded using one or more "code units".