Chernorizets Hrabar

Chernorizets Hrabar (Church Slavonic: Чрьнори́зьць Хра́бръ, Črĭnorizĭcĭ Hrabrŭ, Bulgarian: Черноризец Храбър) was a Bulgarian monk, scholar and writer who worked at the Preslav Literary School in the First Bulgarian Empire at the end of the 9th and the beginning of the 10th century. He is credited as the author of On the Letters.