charactercode

Charactercode is a term used to describe the numeric representation of characters in digital text. In computing, a charactercode typically refers to a code point—a numeric value assigned to a character within a character set—and the encoding method used to map that code point to a sequence of bytes for storage or transmission.

As a concept, charactercode encompasses both the abstract code point and the concrete encoding (such as UTF-8 or UTF-16) that converts code points to bytes, and it may also include metadata such as endianness or byte order marks.

Code points are organized in a repertoire; for example, Unicode assigns code points up to U+10FFFF. ASCII uses code points 0–127. Encoding schemes determine how code points are represented as bytes: UTF-8 uses variable length, UTF-16 uses 16-bit units, and UTF-32 uses fixed 32-bit units.

History of the concept reflects the evolution of text representation in computing. Early computers used many incompatible encodings (ASCII, ISO 8859, Shift JIS, and others). The Unicode standard and its UTF encodings were developed to unify text representation across platforms. Applications must interpret charactercode consistently to display, sort, search, and interchange text.

Common challenges include legacy encodings, text normalization, combining characters, surrogate pairs in UTF-16, endianness, and byte order mark handling. In practice, UTF-8 is dominant on the web, while Unicode normalization forms ensure that visually identical text is treated equivalently by software. See also character encoding, Unicode, and ASCII for related concepts.