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ISO/IEC 10646

Abstract

ISO/IEC 10646:2003 specifies the Universal Multiple-Octet Coded Character Set (UCS). It is applicable to the representation, transmission, interchange, processing, storage, input and presentation of the written form of the languages of the world as well as additional symbols.

ISO/IEC 10646:2003

• specifies the architecture of ISO/IEC 10646:2003;
• defines terms used in ISO/IEC 10646:2003;
• describes the general structure of the coded character set;
• specifies the Basic Multilingual Plane (BMP) of the UCS;
• specifies supplementary planes of the UCS: the Supplementary Multilingual Plane (SMP), the Supplementary Ideographic Plane (SIP) and the Supplementary Special-purpose Plane (SSP);
• defines a set of graphic characters used in scripts and the written form of languages on a world-wide scale;
• specifies the names for the graphic characters of the BMP, SMP, SIP, SSP and their coded representations;
• specifies the four-octet (32-bit) canonical form of the UCS: UCS-4;
• specifies a two-octet (16-bit) BMP form of the UCS: UCS-2;
• specifies a multiple byte (one to four) byte transformation UTF-8 for use with ISO 646 (ASCII) byte-oriented environments;
• specifies a two 16-bit form and associated transformation UTF-16 for supplementary characters;
• specifies collection identifiers for selected set of character subsets;
• specifies the coded representations for control functions;
• specifies the management of future additions to this coded character set;
• incorporates the Unicode bi-directional algorithm and normalization forms by reference.

The UCS is a coding system different from that specified in ISO/IEC 2022. A graphic character will be assigned only one code position in ISO/IEC 10646:2003, located either in the BMP or in one of the supplementary planes.

NOTE - The Unicode Standard, Version 5.0 includes a set of characters, names, and coded representations that are identical with those in ISO/IEC 10646:2003. It additionally provides details of character properties, processing algorithms, and definitions that are useful to implementers. Version 5.0 strengthens Unicode support for worldwide communication, software availability, and publishing.

By defining a consistent way of encoding multilingual text ISO/IEC 10646:2003 enables the exchange of data internationally. The information technology industry gains data stability, greater global interoperability and data interchange. ISO/IEC 10646:2003 has been widely adopted in new Internet and W3C protocols and mark up languages such as XML and HTML, and implemented in modern operating systems and computer programming languages. This edition covers over 100,000 characters from the world's scripts.

Approved international standards and other specifications that are now freely available include:  

Revision information

The ISO/IEC 10646:2003 edition has the following amendments since its publication which are also freely available:

There are two amendments for ISO/IEC 10646:2003 edition and an FCD that are in progress in SC2:

Previous Editions

Two previous editions of ISO/IEC 10646 were published earlier but has been withdrawn since the publication of ISO/IEC 10646:2003 edition:

1.     The ISO/IEC 10646-1 standard "Universal Multiple-Octet Coded Character Set (UCS) - Part 1: Architecture and Basic Multilingual Plane (BMP)", second edition was published March 2000.

2.     The first edition of IS 10646-1 was published in May 1993.

Here is a list of the earlier withdrawn editions specific to ISO/IEC 10646 and their amendments/corrigenda:

ISO/IEC 10646-1:1993 Information technology -- Universal Multiple-Octet Coded Character Set (UCS) -- Part 1: Architecture and Basic Multilingual Plane

ISO/IEC 10646-1:1993/Amd 1:1996 Transformation Format for 16 planes of group 00 (UTF-16)

ISO/IEC 10646-1:1993/Cor 1:1996

ISO/IEC 10646-1:1993/Amd 2:1996 UCS Transformation Format 8 (UTF-8)

ISO/IEC 10646-1:1993/Cor 2:1998

ISO/IEC 10646-1:1993/Amd 3:1996

ISO/IEC 10646-1:1993/Amd 4:1996

ISO/IEC 10646-1:1993/Amd 5:1998 Hangul syllables

ISO/IEC 10646-1:1993/Amd 6:1997 Tibetan

ISO/IEC 10646-1:1993/Amd 7:1997 33 additional characters

ISO/IEC 10646-1:1993/Amd 8:1997

ISO/IEC 10646-1:1993/Amd 9:1997 Identifiers for characters

ISO/IEC 10646-1:1993/Amd 10:1998 Ethiopic

ISO/IEC 10646-1:1993/Amd 11:1998 Unified Canadian Aboriginal Syllabics

ISO/IEC 10646-1:1993/Amd 12:1998 Cherokee

ISO/IEC 10646-1:1993/Amd 13:1998 CJK unified ideographs with supplementary sources

ISO/IEC 10646-1:1993/Amd 16:1998 Braille patterns

ISO/IEC 10646-1:1993/Amd 17:1999 CJK Unified Ideographs Extension A

ISO/IEC 10646-1:1993/Amd 18:1999 Symbols and other characters

ISO/IEC 10646-1:1993/Amd 19:1998 Runic

ISO/IEC 10646-1:1993/Amd 20:1998 Ogham

ISO/IEC 10646-1:1993/Amd 21:1999 Sinhala

ISO/IEC 10646-1:1993/Amd 23:1999 Bopomofo Extended and others characters

ISO/IEC 10646-1:2000 Information technology -- Universal Multiple-Octet Coded Character Set (UCS) -- Part 1: Architecture and Basic Multilingual Plane

ISO/IEC 10646-2:2001 Information technology -- Universal Multiple-Octet Coded Character Set (UCS) -- Part 2: Supplementary Planes

ISO/IEC 10646-1:2000/Amd 1:2002 Mathematical symbols and other characters

ISO/IEC TR 15285

WG2 has in cooperation with SC18 developed a technical report (freely available): ISO/IEC TR 15285 - An operational model for characters and glyphs.

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