A joint initiative of the International Organization for Standardization (ISO) and the Unicode Consortium to develop a 32-bit character set capable of encoding all written languages. ISO 10646 defines the Universal Character Set (UCS), into which all Unicode Transformation Format (UTF) code sets map. UCS-4 is a four-octet code set into which UTF-32 maps and UCS-2 is a two-byte code set into which UTF-16 maps. UCS-1 encodes all characters in byte sequences varying from one to five bytes. See also bit, byte, code set, octet, and Unicode.