The Cyrillic script is derived from the Greek uncial script letters, augmented by ligatures and consonants from the older Glagolitic alphabet for sounds not found in Greek. Glagolitic and Cyrillic were formalized by the Byzantine Saints Cyril and Methodius and their disciples, such as Saints Naum, Clement, Angelar, and Sava.
The Cyrillic script is a product of the collaboration between the Greek uncial script and the Glagolitic alphabet, with the addition of ligatures and consonants to represent sounds not found in Greek. This system was developed by Byzantine Saints Cyril and Methodius and their disciples, including Naum, Clement, Angelar, and Sava.