Э э is a letter found in three Slavic languages: Russian, Belarusian, and West Polesian. It represents the vowels and, as the e in the word "editor". In other Slavic languages that use the Cyrillic script, the sounds are represented by Ye (Е е), which represents in Russian and Belarusian in initial and postvocalic position or and palatalizes the preceding consonant. This letter closely resembles and should not be confused with the older Cyrillic letter Ukrainian Ye, of which Э is a reversed version.

The Cyrillic script, Slavonic script or simply Slavic script is a writing system used for various languages across Eurasia. It is the designated national script in various Slavic, Turkic, Mongolic, Uralic, Caucasian and Iranic-speaking countries in Southeastern Europe, Eastern Europe, the Caucasus, Central Asia, North Asia, and East Asia, and used by many other minority languages.