Early Cyrillic alphabet - Wikipedia
https://en.wikipedia.org/wiki/Early_Cyrillic_alphabetThe Early Cyrillic alphabet, also called classical Cyrillic or paleo-Cyrillic, is a writing system that was developed in the First Bulgarian Empire during the late 9th century on the basis of the Greek alphabet for the Slavic peoples living near the Byzantine Empire in South East and Central Europe. It was used by Slavic peoples in South East, Central and Eastern Europe.
Russian alphabet - Wikipedia
https://en.wikipedia.org/wiki/Russian_alphabet50 rader · The Russian alphabet (Russian: ру́сский алфави́т, tr. russkiy alfavit, IPA: [ˈruskʲɪj ɐlfɐˈvʲit] or, more traditionally, Russian: ру́сская а́збука, tr. russkaya azbuka, IPA: [ˈruskəjə ˈazbʊkə]) was derived from Cyrillic script for Old Church Slavonic language. Initially an old variant of the Bulgarian alphabet, it became used in the Kievan Rus' since ...