Chernorizets Hrabar (Old Church Slavonic: Чрьнори́зьць Хра́бръ, Črĭnorizĭcĭ Hrabrŭ) was a Bulgarian monk, scholar and writer who worked at the Preslav Literary School at the end of the 9th and the beginning of the 10th century, developing Medieval Bulgarian literature and spreading Old Church Slavonic.
His appellation is correctly translated as "Hrabar, the Black Robe Wearer" (i.e., Hrabar The Monk), "Hrabar" ("Hrabr") being his given name, chernorizets being the lowest rank in the monastic hierarchy. Sometimes he is referred to as "Chernorizets the Brave", brave being the translation of the given name.
No biographical information is available about him, but his name is usually considered to be a pseudonym used by one of the other famous men of letters at the Preslav Literary School or may be even by Tsar Simeon I of Bulgaria (893-927), since normally monks assume Christian names of biblical or early Christian onomastics.
Literary work 
Chernorizets Hrabar is (as far as is known) the author of only one literary work, "An Account of Letters" (Old Church Slavonic: О писмєньхъ, O pismenech), one of the most admired and popular works of literature written in Old Church Slavonic. The work was supposedly written shortly after the Preslav Ecclesiastical People's Council in 893 and is the only known medieval literary work to quote the exact year of the invention of the Glagolitic alphabet (855).
In An Account of Letters, Chernorizets Hrabar defends the alphabet against its Greek critics and proves not only its right to existence but also its superiority to the Greek alphabet arguing that the Greek letters are neither the oldest known to man, nor divine. At the same time Chernorizets Hrabar opposes Glagolitic dogmatists and makes several suggestions as to how the alphabet can be further improved.
He also provided information critical to Slavonic palaeography with his mention that the pre-Christian Slavs employed "strokes and incisions" (Old Church Slavonic: чръты и рѣзы, črъty i rězy), translated as "tallies and sketches" below) writing that was, apparently, insufficient properly to reflect the spoken language. It is thought that this may have been a form of runic script but no authentic examples are known to have survived.
The manuscript of An Account of Letters has been preserved in some 80 copies, the oldest of which dates back to 1348 and was made by the monk Laurentius for Tsar Ivan Alexander of Bulgaria. The work has also been printed in Vilnius (1575–1580), Moscow (1637), Saint Petersburg (1776), Supraśl (1781).
Excerpt from An Account of Letters 
- Being still pagans, the Slavs did not have their own letters, but read and communicated by means of tallies and sketches. After their baptism they were forced to use Roman and Greek letters in the transcription of their Slavic words but these were not suitable ... At last, God, in his love for mankind, sent them St. Constantine the Philosopher, called Cyril, a learned and upright man, who composed for them thirty-eight letters, some (24 of them) similar to the Greek, but some (14 of them) different, suitable to express Slavic sounds.
See also 
- Clement of Ohrid
- Constantine of Preslav
- John Exarch
- Cosmas the Priest
- Pre-Christian Slavic writing
- History of Bulgaria
- Simeon I of Bulgaria
- Also transliterated Chernorizetz Hrabar, Chernorizets Hrabr and Crnorizec Hrabar
- A history of East Central Europe: East Central Europe in the Middle Ages, 1000-1500, Jean W. Sedlar, University of Washington Press, 1994, ISBN 0-295-97290-4, p. 430.
- A concise history of Bulgaria, R. J. Crampton, Cambridge University Press, 2005, ISBN 0-521-61637-9,pp. 16-17.