Here's a bit more about them:
* Saints Cyril and Methodius were two Byzantine Greek brothers who lived in the 9th century.
* They were missionaries who travelled to Great Moravia (modern-day Czech Republic and Slovakia) to spread Christianity.
* They realized that translating the Bible and other religious texts into the local language would be more effective than using Latin, the language of the church at the time.
* To achieve this, they adapted the Greek alphabet to the sounds of the Slavic language, creating the Glagolitic alphabet.
* However, they later developed a more efficient and simpler alphabet, which is now known as the Cyrillic alphabet.
While Cyrillic was initially designed for Old Church Slavonic, it has evolved over time and is now used for writing many Slavic languages, including Russian, Bulgarian, Serbian, Ukrainian, Belarusian, and others.