I or Y (И, и) is a letter in the Cyrillic alphabet, representing in Russian and in Ukrainian. It looks like a backwards version of the Latin alphabet's capital N, and is derived from the Greek letter eta (Η, η, pronounced in Ancient Greek but in Modern Greek).

In the early Cyrillic alphabet there was little or no distinction between the letters и (izhei) and і (izhe), descended from the Greek letters η (eta) and ι (iota). They both remained in the alphabetical repertoire because they represented different numbers in the Cyrillic numeral system, eight and ten, and are therefore sometimes referred to as octal I and decimal I.

It is the tenth letter of the Russian alphabet, and in Russian is represents , like the i in machine. Although in isolation it is not preceded by the semivowel like other "soft" vowels (е, ё, ю, and я), in Russian it is considered the soft counterpart to ы, which represents . (In Ukrainian and Belarusian, the sound is represented by the letter і, sometimes called Ukrainian I.)

The letter и is the eleventh letter of the Ukrainian alphabet, and in Ukrainian represents , as in English image.

Belarusian has dispensed entirely with the letter и.

With a breve, it forms the letter й, called I kratkoye ("short I") in Russian or Yot in Ukrainian and represents the Y in English "yet."

It is transliterated from Russian as i, or from Ukrainian as y or i, using different romanization systems. See transliteration of Russian into English and romanization of Ukrainian.

The Cyrillic letters и and я are used in faux Cyrillic typography.

Vowel letters

И | И (lizherenn) | I (cyrillique) | И (Cirillico) | И | И | И | I (Cirílico) | И (кириллица) | И (ћириличко) | И | И