What was the significance of the activities of Cyril and Methodius for the development of Slavic culture?

Cyril and Methodius played an important role in the development of Slavic culture. In 863, they founded the first ordered alphabet and Slavic writing. Along with this, for a long time they lived among the Western and South Slavs, conducted educational work among them and taught literacy. Cyril and Methodius also prevented the German clergy from introducing a ban on the Slavic alphabet and books, translated books from the Greek language, formed the Old Slavonic literary language, Slavic book business.