Yery
Yery (Ы, ы) is a letter in the Cyrillic alphabet. It represents the phoneme /i/ after non-palatalized (hard) consonants in the Belarusian and Russian alphabets. Because of phonological processes, the actual realization of /i/ after hard consonants is retracted to a close central unrounded vowel (IPA [ɨ]).
Like many Cyrillic letters, originally the letter yery was formed from a ligature—between Yer Ъ and Izhe (then I) or Izhei (then Н, now И). In ancient manuscripts, it is almost without exception found as ЪІ or ЪН. Once the letters Ъ and Ь subsequently lost their values as vowels from the Slavonic language, the current form Ы evolved.
The yery is theoretically never capitalized because no words start with it, but Cyrillic type faces do normally provide an uppercase form for setting type in all caps.