Bulgarian was the first Slavic language to be written: it starts to appear in writing during the 9th century in the Glagolitic alphabet, which was gradually replaced by an early version of the Cyrillic alphabet over the following centuries.
Several Cyrillic alphabets with 28 to 44 letters were used in the early and middle 19th century during the efforts on the codification of Modern Bulgarian until an alphabet with 32 letters, proposed by Marin Drinov, gained prominence in the 1870s.
It was used until the orthographic reform of 1945, when the letters yat (uppercase Ѣ, lowercase ѣ) and yus (uppercase Ѫ, lowercase ѫ) were removed from its alphabet, reducing the number of letters to 30.
Thus, there are 30 letters in the modern Bulgarian alphabet. Six of the letters are vowels: е, и, а, ъ, о and у. The rest are consonants.
Most letters in the Bulgarian alphabet stand for just one specific sound. Five letters stand for sounds written in English with two or more letters. These letters are ч (ch), ш (sh), щ (sht), ю (yu) and я (ya).
The letter ь marks the softening (palatalization) of consonants, but the letter itself is not pronounced.
The accented letter Ѝ is used to distinguish the conjunction 'и' (and) from the pronoun 'Ѝ' (her). It is not considered a separate letter but rather a special form of И.
Bulgarian is usually described as having a phonemic orthography, meaning that words are spelled the way they are pronounced. This is largely true, although there are a few exceptions.