<ref>{{Cite journal|last=Crispin|first=M.|date=April 2005|title=UTF-9 and UTF-18 Efficient Transformation Formats of Unicode|url=http://dx.doi.org/10.17487/rfc4042}}</ref> A '''variable-width encoding''' is a type of [[character encoding]] scheme in which codes of differing lengths are used to encode a [[character set]] (a repertoire of symbols) for representation in a [[computer]].<ref>{{Cite journal|last=Crispin|first=M.|date=April 2005|title=UTF-9 and UTF-18 Efficient Transformation Formats of Unicode|url=http://dx.doi.org/10.17487/rfc4042}}</ref> Most common variable-width encodings are '''multibyte encodings''', which use varying numbers of [[byte]]s ([[octet (computing)|octets]]) to encode different characters.
(Some authors, notably in Microsoft documentation, use the term ''multibyte character set,'' which is a [[misnomer]], because representation size is an attribute of the encoding, not of the character set.)
