Modern KOI code pages are 8-bit extensions of ASCII. This family of encodings is also known as KOI8, KOI 8 and KOI-8.
The family members are:
- KOI8-R for Russian and Bulgarian.
- KOI8-U and KOI8-RU for Ukrainian, Belorussian and Russian.
- KOI8-T for Tajik.
- KOI8-CS for Czech and Slovak (ČSN (Czech technical standard) 369103. Devised by the Comecon. This encoded Latin with diacritics, as used in Czech and Slovak, rather than Cyrillic, but the basic idea was the same - text should remain legible with the 8-th bit cleared, thus e.g. Č became C etc.).
- KOI8-O for Old Russian.
Read more about this topic: KOI Character Encodings