In modern Russian, the hard sign is kind of rare. But did you know that it used to be quite common? That’s right! It was just as common as the soft sign until the Russian Revolution. After the Revolution, a spelling reform took place and the hard sign was taken away where it wasn’t needed.
If you are new to the Russian language, you might not understand the modern uses of the hard and soft signs. So let’s take a look at them real quick.
The soft sign (ь) is used to mark palatalized consonants, as in the word день “day”, which is pronounced with a final, soft /n/. The sign makes no sound on its own, and instead modifies the letter before it (in this case <н>). This is very important in Russian, because palatalization is phonemic. For example, compare the words брат and брать. брат “brother” is pronounced with a final, hard /t/. брать “to take” is pronounced with a final, soft /t/.
There are places in modern Russian where the soft sign is not needed, but written anyways. When a soft sign occurs after a hard-only consonant (such as <ж> or <ш>), it has no effect on this consonant. The most common example of this is verbs inflected in the second person singular form: ты играешь “you play.” The soft sign has no effect on the <ш> letter. It remains hard no matter what. This is purely traditional spelling.
The hard sign (ъ) is used to mark hard consonants, but it no longer occurs at the ends of words. It can now only occur before a soft vowel (я е ё и ю). In these positions, the hard sign is used to denote that the consonant before the soft vowel is hard.
You must always remember that Russian’s soft consonants are not simply a normal consonant plus a /y/ sound. They are palatalized, which means that the /y/ sound is mixed in with the consonant. When a hard sign comes before a soft vowel, the /y/ sound is not mixed with the consonant – thus it is not soft. It’s hard :).
Compare the words сесть and съесть. сесть “to sit down” is pronounced with a soft /s/ at the beginning. съесть “to eat” is pronounced with a hard /s/ followed by a /y/ sound at the beginning.
So now you know how the hard and soft signs are used in modern Russian. BUT, did you know that both of these signs used to actually denote sounds?!
Old Russian was a language of open syllables, which means that most of the modern consonant clusters didn’t exist back then and words couldn’t end in a consonant. Kind of like modern Japanese.
The hard sign (ъ) used to represent a short back vowel, commonly transcribed as /ŭ/. So it was probably pronounced like the /u/ in boot, just a lot shorter.
The soft sign (ь) used to represent a short front vowel, commonly transcribed as /ĭ/. So it was probably pronounced like the /i/ in meet, just a lot shorter.
As Old Russian developed and progressed into Middle Russian and then Modern Russian, these short vowels (known as yers) were lost. It is believed that the actual pronunciation of the final <ъ> completely died out between the 15th and 19th centuries.
The short front vowel, /ĭ/, changed to <е~ё> in strong positions, and triggered palatalization in other positions (still written as <ь>).
The short back vowel, /ŭ/, changed to <о> in strong positions, or was completely lost. However, it was still written at the end of words until the spelling reform.
сънъ /’sŭ.nŭ/ became сонъ “sleep, nom. sg.” > now written as сон
съна /sŭ’na/ became сна “sleep, gen. sg.”
къдѣ /kŭ’dě/ became гдѣ “where” > now written as где (the loss of <ѣ> (yat) shall be saved for another post :))
человѣкъ “person” > человек
годъ “year” > год
So: the final hard sign had no pronunciation and its removal simplified Russian orthography. It was purely a reminder of Russian’s open-syllable past, and Russians have saved a lot of ink since its demise!