KPS 9566 is a North Korean standard which specifies an ISO 2022-compliant 94x94 two-byte coded character set for the Hangul writing system used for the Korean language. First published in 1993, it has since undergone several revisions in 1997, 2000 and 2003, mainly to enhance compatibility with Unicode. These are commonly indicated by specifying the year (KPS 9566-97, 9566-2000 and 9566-2003).
In principle, KPS 9566 is similar to the South Korean KS X 1001 encoding, except that it uses a different ordering of characters to conform with North Korean lexicographical ordering standards. It is also notable for its inclusion of several special characters from North Korean political life, including the following:
Due to these special characters, there is currently no full round-trip compatibility between KPS 9566 and Unicode. This would require adding these characters to the Universal Character Set, which the Unicode Consortium refused in 2000.