Related Research Articles
GB 18030 is a Chinese government standard, described as Information Technology — Chinese coded character set and defines the required language and character support necessary for software in China. GB18030 is the registered Internet name for the official character set of the People's Republic of China (PRC) superseding GB2312. As a Unicode Transformation Format, GB18030 supports both simplified and traditional Chinese characters. It is also compatible with legacy encodings including GB2312, CP936, and GBK 1.0.
The Ideographic Research Group (IRG), formerly called the Ideographic Rapporteur Group, is a subgroup of Working Group 2 (WG2) of ISO/IEC JTC 1/SC 2, the subcommittee of the Joint Technical Committee of ISO and IEC which is responsible for developing standards within the field of coded character sets. IRG is composed of experts from China, Japan, South Korea, Vietnam and other countries and regions that use Han characters, as well as experts representing the Unicode Consortium. The group is responsible for coordinating the addition of new CJK unified ideographs to the Universal Multiple-Octet Coded Character Set and the Unicode Standard. The group meets twice a year for 4-5 days each time, and reports its activity to the subsequent meeting of WG2.
The Chinese, Japanese and Korean (CJK) scripts share a common background, collectively known as CJK characters. During the process called Han unification, the common (shared) characters were identified and named CJK Unified Ideographs. As of Unicode 15.1, Unicode defines a total of 97,680 characters.
CJK Unified Ideographs Extension-A is a Unicode block containing rare Han ideographs submitted to the Ideographic Research Group between 1992 and 1998, plus ten ideographs added in Unicode 13.0 which had previously been mistakenly unified with others.
CJK Symbols and Punctuation is a Unicode block containing symbols and punctuation used for writing the Chinese, Japanese and Korean languages. It also contains one Chinese character.
Kangxi Radicals is a Unicode block. In version 3.0 (1999), this separate Kangxi Radicals block was introduced which encodes the 214 radicals in sequence, at U+2F00–2FD5. These are specific code points intended to represent the radical qua radical, as opposed to the character consisting of the unaugmented radical; thus, U+2F00 represents radical 1 while U+4E00 represents the character yī meaning "one". In addition, the CJK Radicals Supplement block (2E80–2EFF) was introduced, encoding alternative forms taken by Kangxi radicals as they appear within specific characters. For example, ⺁ "CJK RADICAL CLIFF" (U+2E81) is a variant of ⼚ radical 27 (U+2F1A), itself identical in shape to the character consisting of unaugmented radical 27, 厂 "cliff" (U+5382).
CJK Unified Ideographs is a Unicode block containing the most common CJK ideographs used in modern Chinese, Japanese, Korean and Vietnamese characters. When compared with other blocks containing CJK Unified Ideographs, it is also referred to as the Unified Repertoire and Ordering (URO).
CJK Unified Ideographs Extension B is a Unicode block containing rare and historic CJK ideographs for Chinese, Japanese, Korean, and Vietnamese submitted to the Ideographic Research Group between 1998 and 2000, plus seven gongche characters for kunqu added in Unicode 13.0, and two characters for the Macao Supplementary Character Set added in Unicode 14.0.
CJK Unified Ideographs Extension C is a Unicode block containing rare and historic CJK ideographs for Chinese, Japanese, Korean, and Vietnamese submitted to the Ideographic Research Group between 2002 and 2006, plus five "urgently needed" characters added in Unicode versions 14.0 and 15.0, some of which had previously been mistakenly unified with other characters.
CJK Unified Ideographs Extension D is a Unicode block containing uncommon CJK ideographs for Chinese, Japanese, Korean, and Vietnamese, some of which are in current use. Much smaller than most Unicode blocks for CJK unified ideographs, Extension D consists of characters which were submitted to the Ideographic Research Group as "urgently needed characters" between 2006 and 2009. Characters submitted during the same period which were needed less urgently were included in CJK Unified Ideographs Extension E instead.
CJK Compatibility Ideographs Supplement is a Unicode block containing Han characters used only for roundtrip compatibility mapping with planes 3, 4, 5, 6, 7, and 15 of CNS 11643-1992.
CJK Compatibility Ideographs is a Unicode block created to contain Han characters that were encoded in multiple locations in other established character encodings, in addition to their CJK Unified Ideographs assignments, in order to retain round-trip compatibility between Unicode and those encodings. Such encodings include:
Enclosed CJK Letters and Months is a Unicode block containing circled and parenthesized Katakana, Hangul, and CJK ideographs. Also included in the block are miscellaneous glyphs that would more likely fit in CJK Compatibility or Enclosed Alphanumerics: a few unit abbreviations, circled numbers from 21 to 50, and circled multiples of 10 from 10 to 80 enclosed in black squares.
CJK Compatibility Forms is a Unicode block containing vertical glyph variants for east Asian compatibility. Its block name in Unicode 1.0 was CNS 11643 Compatibility, in reference to CNS 11643.
CJK Compatibility is a Unicode block containing square symbols encoded for compatibility with East Asian character sets. In Unicode 1.0, it was divided into two blocks, named CJK Squared Words (U+3300–U+337F) and CJK Squared Abbreviations (U+3380–U+33FF).
Variation Selectors is the block name of a Unicode code point block containing 16 variation selectors used to specify a glyph variant for a preceding character. They are currently used to specify standardized variation sequences for mathematical symbols, emoji symbols, 'Phags-pa letters, and CJK unified ideographs corresponding to CJK compatibility ideographs. At present only standardized variation sequences with VS1, VS2, VS3, VS15 and VS16 have been defined; VS15 and VS16 are reserved to request that a character should be displayed as text or as an emoji respectively.
CJK Unified Ideographs Extension E is a Unicode block containing rare and historic CJK ideographs for Chinese, Japanese, Korean, and Vietnamese submitted to the Ideographic Research Group between 2006 and 2013, excluding the characters submitted as "urgently needed" between 2006 and 2009, which were included in CJK Unified Ideographs Extension D.
CJK Unified Ideographs Extension F is a Unicode block containing rare and historic CJK ideographs for Chinese, Japanese, Korean, and Vietnamese, as well as more than a thousand Sawndip characters for writing the Zhuang language, which were submitted to the Ideographic Research Group between 2012 and 2015.
CJK Unified Ideographs Extension G is a Unicode block containing rare and historic CJK Unified Ideographs for Chinese, Japanese, Korean, and Vietnamese which were submitted to the Ideographic Research Group during 2015. It is the first block to be allocated to the Tertiary Ideographic Plane.
CJK Unified Ideographs Extension I is a Unicode block comprising CJK Unified Ideographs included in drafts of an amendment to China's GB 18030 standard circulated in 2022 and 2023, which were fast-tracked into Unicode in 2023.
References
- ↑ "Unicode character database". The Unicode Standard. Retrieved 2023-07-26.
- ↑ "Enumerated Versions of The Unicode Standard". The Unicode Standard. Retrieved 2023-07-26.
- ↑ "18.1: Han (§ Blocks Containing Han Ideographs)" (PDF). The Unicode Standard: Core Specification. Version 15.0. Unicode Consortium. pp. 741–744. 2022. ISBN 978-1-936213-32-0.