Macedonian language
The Macedonian speech around Thessaloniki was the basis for the formation of the Old Slavic language and literacy. What characterizes the history of the Macedonian language is its radical change that occurred from the 10th century onwards. Similar changes affected the Bulgarian language and the eastern dialects of the Serbian language. Those fundamental changes led to a small sharing of grammatical features between the Old Slavic and Macedonian languages, so as a result the Macedonian recension of the Old Slavic language was created. Well-known centers of Macedonian review are the Ohrid Literary School and the Lesnov Literary School.