Old Church Slavonic or Old Slavonic is the first Slavic literary language and the oldest extant written Slavonic language attested in literary sources. It belongs to the Eastern South Slavic subgroup
A page from Codex Zographensis, 10th or 11th century.
Example of the Cyrillic alphabet: excerpt from the manuscript Vidin Miscellany, written in Middle Bulgarian, 1360
A page from the Flowery Triodion (Triod' cvetnaja), a Polish book printed in Kraków in about 1491, one of the oldest printed Byzantine-Slavonic books, National Library of Poland
A page from the Gospel of Miroslav, Serbian medieval manuscript, a 12th-century Byzantine-Slavonic book, National Library of Serbia
Yat or jat is the thirty-second letter of the old Cyrillic alphabet.
Pre-revolution typewriter with Yat on the bottom row, between Ч and С.
Cover of 1880 edition of Turgenev's Fathers and Sons, with yat in the title: дѣти is spelled дети.
An antiques shop named with the pseudoarchaic orthography "антиквариатѣ" (current spelling : "антиквариат", pre-reform spelling : "антикваріатъ").
Vĕstnik časopis (14 January 1854) with extensive use of Yat