The CCITT Chinese Primary Set[2] is a multi-byte graphic character set for Chinese communications created for the Consultative Committee on International Telephone and Telegraph (CCITT) in 1992.
[3] It is defined in ITU T.101, annex C, which codifies Data Syntax 2 Videotex.
[3] The Unihan database references GB 8565.2 as the mainland Chinese source of several hanzi included in Unicode.
[3][4] These CCITT hanzi extensions have on occasion been mistaken for standard GB 8565.2 characters, including in previous revisions of the Unihan database.
[4] This collides with the vertical presentation forms included in other extensions such as Mac OS Simplified Chinese[10] and GB 18030.